Parental history of hypertension and dietary intakes in early adolescent offspring: a population-based study

We investigated the cross-sectional association between parental history of hypertension and dietary intakes among early adolescent schoolchildren. A total of 1845 participants aged 12 years had complete data on diet and parental medical history, and thus they were included in the final analyses. Dietary data were assessed from validated semi-quantitative food-frequency questionnaires. Parents completed questionnaires about their medical conditions. Cases where the biological mother and/or father had hypertension were classified as positive parental history of hypertension. After multivariable adjustment, participants with positive versus negative parental history of hypertension had 33% greater likelihood of consuming soft drinks ⩾1 per week. Boys with a parental history versus boys without a parental history of hypertension consumed more energy-dense, nutrient-poor foods: 379.4 g per day and 318.0 g per day, respectively, P=0.02. Girls with a positive versus a negative parental history consumed more vegetables: 164.1 versus 142.6 g per day, P=0.01. Significant associations were not observed between those with and those without a positive parental history in mean dietary intakes of carbohydrates, fats, sugars and sodium. Children with a positive parental history of hypertension were 67% more likely to simultaneously engage in three unhealthy lifestyle behaviors (excessive recreational screen viewing, high consumption of snacks and and high consumption of soft drinks). Parental hypertension was associated with unhealthy dietary behaviors among offspring, including higher consumption of soft drinks and energy-dense, nutrient-poor foods.

Diet quality is prospectively associated with incident impaired fasting glucose in older adults

AIMS

Dietary modifications may play an important role in the prevention of diabetes. We aimed to assess the temporal association between diet quality and both impaired fasting glucose and Type 2 diabetes among older adults.

METHODS

A total of 2564 participants aged 49+ years at baseline were examined between 1992 and 1994 and 2002-2004 and had their fasting blood glucose measured. Dietary data were collected using a semi-quantitative food frequency questionnaire. A modified version of the Healthy Eating Index for Australians was developed to determine Total Diet Score. Incident diabetes (or impaired fasting glucose) was defined in participants at risk who were newly diagnosed by a physician during the follow-up or found to have a fasting blood glucose level ≥ 7.0 mmol/l (or 6.1-6.9 mmol/l).

RESULTS

After adjusting for age, sex, current smoking, body mass index, hypertension and serum triglycerides, comparing highest with lowest tertile of total diet score, a significant 75% decrease in risk of incident impaired fasting glucose was observed in men (P(trend) = 0.02). Also, in men, each two-point increase in Total Diet Score was associated with a 52% reduction in the 10-year incidence of impaired fasting glucose, (OR 0.48, 95% CI 0.33-0.69). No significant associations were observed among women or with the 10-year incidence of diabetes.

CONCLUSIONS

Greater compliance with published dietary guidelines (better diet quality) was associated with a reduced risk of pre-diabetes in men, but not women.

Relationship of Type 2 diabetes to the prevalence, incidence and progression of age-related hearing loss

AIMS

Type 2 diabetes and associated microvascular abnormalities are postulated to affect hearing. Our study reports on the relationship between Type 2 diabetes and the prevalence, 5-year incidence and progression of hearing impairment in a representative, older, Australian population.

METHODS

The Blue Mountains Hearing Study is a population-based survey of age-related hearing loss conducted in a defined suburban area, west of Sydney. Hearing loss was defined as the pure-tone average of frequencies 0.5, 1.0, 2.0 and 4.0 kHz > 25 decibels hearing level (dB HL) in the better ear (bilateral hearing loss). Type 2 diabetes was defined from reported physician-diagnosed diabetes or fasting blood glucose > or = 7.0 mmol/l.

RESULTS

Age-related hearing loss was present in 50.0% of diabetic participants (n = 210) compared with 38.2% of non-diabetic participants (n = 1648), odds ratio (OR) 1.55 [95% confidence interval (CI) 1.11-2.17], after adjusting for multiple risk factors. A relationship of diabetes duration with hearing loss was also demonstrated. After 5 years, incident hearing loss occurred in 18.7% of participants with, and 18.0% of those without diabetes, adjusted OR 1.01 (CI 0.54-1.91). Progression of existing hearing loss (> 5 dB HL), however, was significantly greater in participants with newly diagnosed diabetes (69.6%) than in those without diabetes (47.8%) over this period, adjusted OR 2.71 (CI 1.07-6.86).

CONCLUSIONS

Type 2 diabetes was associated with prevalent, but not incident hearing loss in this older population. Accelerated hearing loss progression over 5 years was more than doubled in persons newly diagnosed with diabetes. These data explore further reported links between Type 2 diabetes and age-related hearing loss.

Association between self-rated health and incident severe hypertension among men: a population-based cohort study

INTRODUCTION

Self-rated health (SRH) is a consistent predictor of cardiovascular disease and mortality. However, the intermediate biological mechanisms behind this association are not clear. We examined the longitudinal relationship between SRH and incident severe hypertension.

METHODS

We studied a population-based cohort of 1,298 participants (mean age 62.5 years, range 49-84 years), at the baseline examination (1992-1994) residing in the Blue Mountains region, west of Sydney, Australia, and re-examined after five years (1997-1999). Main outcome-of-interest was incident severe hypertension (systolic blood pressure [BP] 160 mmHg or above, diastolic BP 100 mmHg or above, or a combination of self-reported hypertension diagnosis and use of antihypertensive medications) among baseline individuals without severe hypertension.

RESULTS

Among men, those with fair/poor SRH had significantly higher odds of incident severe hypertension, compared to individuals with excellent SRH. Multivariable odds-ratio (OR) (95 percent confidence intervals [CI]) comparing fair/poor SRH to excellent SRH was 1.93 (1.04-3.56) (p-trend was 0.03). This association was not observed in women comparing fair/poor SRH to excellent SRH: OR 0.96, 95 percent CI 0.57-1.62 (p-trend was 0.70). Subgroup analyses stratified by age, smoking, body mass index, diabetes mellitus and BP categories, supported this male gender-specific pattern of association.

CONCLUSION

This data suggests an association between poor SRH and incident hypertension among men, but not among women. These results suggest that at least part of the previously-reported association between poor SRH and mortality may be mediated by its relation to incident severe hypertension.

Complement factor H polymorphisms, renal phenotypes and age-related macular degeneration: the Blue Mountains Eye Study

Complement factor H (CFH) is a key regulator of the alternative pathway of complement and its mutations have been associated with membranoproliferative glomerulonephritis type II, atypical hemolytic uremic syndrome and age-related macular degeneration (AMD), suggesting that alternative pathway dysregulation is a common pathogenetic feature of these ocular and renal conditions. In this study we tested the hypothesis that common CFH variants have a global role in renal function in the Australian population-based Blue Mountains Eye Study (BMES). We replicated the association of I62V with estimated glomerular filtration rate (GFR; P=0.017) and creatinine clearance (CRCL; P=0.015). The minor allele of I62V (G) was deleterious: adding one copy of the G allele decreased GFR/CRCL by approximately 0.98 ml min(-1) per 1.73 m(2) (95% confidence interval (CI): 0.97, 0.99). We also replicated the association of Y402H with AMD and provided an unbiased estimate of population attributable risk (PAR). The minor allele of Y402H (C) was deleterious: the odds ratio estimate of CC genotype compared to TT was 1.87 (95% CI: 1.44, 2.45). The PAR of the C allele was estimated as 0.22 (95% CI: 0.15, 0.28). In summary, in the BMES population we confirmed the association between I62V and renal function, as measured by the estimated GFR, plus the association of Y402H with both early- and late-stage AMD.

Population prevalence and incidence of Parkinson’s disease in an Australian community

BACKGROUND

Parkinson's disease (PD) is the second most common neurodegenerative disorder affecting older individuals. Few studies have determined the prevalence and incidence of this disease in Australia. The aim of the study was to estimate the prevalence and 10-year incidence of PD in the Australian community.

METHODS

In the Blue Mountains Eye Study (BMES), a population-based health survey of Australian residents aged 49 years or more, we determined the cross-sectional prevalence (BMES2, 1997-1999, n = 3509) and 10-year incidence (BMES1, 2 and 3, 1992-1994, 1997-1999 and 2002-2004, respectively, n = 2545) of PD. We screened participants who took PD medications. PD diagnosis was confirmed by contacting the participant's medical/general practitioners.

RESULTS

Nineteen new cases of PD were identified over the 10-year period, a 10-year incidence of 0.84% (95% confidence interval (CI) 0.54-1.33%). In the cross-sectional study, 16/3509 participants were confirmed to have PD (0.46%), with age-specific prevalence rates of 0.48% in persons aged 60-69 years, 0.82% for ages 70-79 years and 0.56% in persons aged 80 years or older. No PD cases were identified among participants less than 60 years of age. When age standardized to the 2001 Australian population, the prevalence of PD was 362 per 100,000 (95%CI 183-541) among persons aged 50 years or older and 104 per 100,000 for the Australian population at all ages, assuming no prevalent cases in persons aged less than 50 years.

CONCLUSION

This study estimates a 0.46% (95%CI 0.23-0.68) prevalence of PD patients treated with medications aged 50 years or older and a 10-year incidence of 0.84% (95%CI 0.54-1.33).

Body mass index and its effects on retinal vessel diameter in 6-year-old children

PURPOSE

To examine the relationship between body mass index (BMI) and other anthropometric measures with retinal vessel diameter in children.

METHODS

A random cluster sample of 34 schools was selected in the Sydney metropolitan area during 2003-04, and 1740 children aged 6 years participated in The Sydney Childhood Eye Study. Retinal images were taken and vessel diameter was measured using a computer-imaging program. Anthropometric measures, including weight, height, waist circumference, BMI and body surface area (BSA), were obtained and defined using standardized protocols. Data on confounders, including ocular parameters, ethnicity, birth parameters and blood pressure, were similarly collected.

RESULTS

Mean BMI was 16.2 kg/m(2) (+/-2.1 s.d.) in 1608 (92.4%) children with complete data. After controlling for age, sex, ethnicity, axial length of the eyeball, birth weight and mean arterial blood pressure, children with BMI above the cardiovascular risk threshold (defined as BMI>16.1 kg/m(2) in boys and BMI>15.9 kg/m(2) in girls) had mean retinal venular diameter 2.1 microm larger than those with BMI below this threshold (P=0.026). Increasing weight and BSA were also positively associated with wider retinal venules. Children in the highest quartile of BMI had mean retinal arteriolar diameter 2.2 microm smaller than those in the lowest quartile. Increasing waist circumference and shorter height were also associated with narrower retinal arterioles.

CONCLUSIONS

In this sample of 6-year-old children, greater BMI, weight and BSA were associated with wider retinal venules, while greater BMI and larger waist circumference were associated with narrower retinal arterioles. These findings suggest a possible effect of increased body mass and adiposity on early microvascular structural alterations in childhood, long before the development of cardiovascular disease.

Change in health-related quality of life after cataract surgery in a population-based sample

PURPOSE

To assess the long-term outcomes from cataract surgery on self-rated health, and health-related quality of life (HRQOL) in a population-based older sample.

METHODS

Participants of the Blue Mountains Eye Study at the baseline (n=3654), 5 (n=2335), and 10-year follow-up (n=1952) were interviewed and examined. Questionnaires included an assessment of self-rated health and HRQOL using the 36-item Short-Form Health Survey (SF-36). Incident cataract surgery was defined if participants had cataract surgery since baseline, and confirmed via lens photographic grading.

RESULTS

There was no statistically significant difference in the proportions of participants who experienced a change in self-rated health between those who had incident cataract surgery (14.1% improvement; 29.1% deterioration) and non-surgical subjects (16.7% improvement; 27.0% deterioration). We found no association between incident cataract surgery and the odds for 10-year change in self-rated health, after multivariate adjustment. In contrast, participants who had incident cataract surgery had a significant improvement in the mean scores of 'mental health' domain of HRQOL (+1.60 vs-2.04, P=0.02) and in the mental component score (+1.43 vs-0.82, P=0.02) than participants who did not undergo surgery. Cataract surgery during follow-up had no significant influence on change in mean scores of other domains or in their physical component score of the SF-36 (-2.57 in participants who had incident surgery vs-2.29 in non-surgical participants, P=0.78).

CONCLUSIONS

We confirmed long-term improvement following cataract surgery in the mental but not in the physical domain of the SF-36 or in answers to a specific self-rated health question.

Five-year incidence and progression of diabetic retinopathy in a defined older population: the Blue Mountains Eye Study

AIMS

To determine 5-year incidence and progression of diabetic retinopathy in an older Australian population-based cohort.

METHODS

During the period 1992-1994, the Blue Mountains Eye Study examined 3654 residents aged 49+years (82.4% of those eligible), living in two urban postcode areas, west of Sydney, Australia. Participants were subsequently invited to attend 5-year follow-up exams. After excluding 543 (14.8%) who died during the follow-up period, 2334 persons (75.0%) were re-examined during 1997-1999. The examination included a comprehensive questionnaire, blood pressure measurement, standardised refraction, Zeiss stereo retinal photographs, and estimation of fasting blood glucose. Diabetic retinopathy was graded from the retinal photographs, using the modified Early Treatment Diabetic Retinopathy Scale classification (15-step scale).

RESULTS

Of participants with diabetes diagnosed at baseline, 150 were re-examined, including 139 with gradable fundus photographs. The cumulative 5-year incidence of diabetic retinopathy was 22.2% before 95% confidence interval (CI) 14.1-32.2%. Retinopathy progression (1+ steps) was documented in 25.9% (95% CI 18.8-34.0%) of participants with retinopathy and gradable photographs at both visits; in 58.3% of these cases, a 2+ -step progression was documented. Progression to proliferative retinopathy occurred in only 4.1% of those with retinopathy at baseline. The only baseline risk factors associated with retinopathy progression, after adjusting for age and gender, were increase in fasting blood glucose, odds ratio (OR) 1.2 (95% CI 1.1-1.4)/mmol/l, and increase in diabetes duration, OR 2.3 (95% CI 1.0-5.3)/10 years.

CONCLUSIONS

These data provide 5-year cumulative incidence of diabetic retinopathy in a defined older population. Increase in diabetes duration and elevated baseline fasting blood glucose level predicted retinopathy incidence.

Prevalence of mitochondrial DNA haplogroups in an Australian population

Mitochondrial DNA (mtDNA) haplogroups are 'neutral polymorphisms' in the mtDNA genome, which have accumulated and persisted along maternal lineages as the human population has migrated worldwide. Three ethnically distinct lineages of human mtDNA populations have been identified: European, characterized by nine haplogroups H, I, J, K, T, U, V, W and X; African, characterized by superhaplogroup L and Asian, characterized by superhaplogroup M. We studied the prevalence of mtDNA haplogroups in participants of the Blue Mountains Eye Study, a large population-based survey of vision conducted between 1991 and 2000 of non-institutionalized permanent residents aged 49 years or older from two suburban postcode areas, west of Sydney, Australia. Total DNA isolated from either hair follicles or blood was available for 3377 of the 3509 participants (96.2%) to determine mtDNA haplogroups by polymerase chain reaction/restriction fragment length polymorphism analysis. Approximately 94.2% of samples could be assigned to one of the nine major European haplogroups, whereas a further 1.2% included the African (L) and Asian (M) superhaplogroups. The five principal haplogroups represented were H (42.9%), U (14.1%), J (10.7%), T (9.2%) and K (8.1%), which together included 85% of this population.

Early age-related maculopathy in eyes after cataract surgery

PURPOSE

To assess age-related maculopathy (ARM) in eyes of patients who had undergone cataract surgery for at least a year.

METHODS

Consecutive patients aged 60+ years who had undergone cataract surgery at Westmead Hospital, Sydney, Australia, during 2001-2003 were examined in 2004. Interview using standardized questionnaires and stereo retinal photography was performed. Retinal photographs were graded using the Wisconsin ARM grading system. The proportions with ARM were compared between surgical and nonsurgical eyes, and between this surgical cohort and the Blue Mountains Eye Study (BMES) population.

RESULTS

Of the 622 eligible patients, 454 (73%) were re-examined, with a mean follow-period of 2.8 years. Surgical eyes had a higher proportion of early ARM compared to nonsurgical eyes (15.2 vs10.3%, P=0.07) and to the early ARM prevalence found in BMES participants of similar age (14.5 vs6.9%, P<0.01), which persisted after age standardization to the BMES population (9.7 vs6.9%, P<0.05).

CONCLUSIONS

We found an increased prevalence of early ARM in surgical eyes of patients 1-3 years after cataract surgery. Whether this increased early ARM prevalence leads to an increased prevalence of late ARM in the long-term warrants further investigation.

Dyslipidaemia and microvascular disease in the retina

PURPOSE

There are few data on the effect of serum lipids on microvascular disease. This study assessed the relationships between serum lipid levels and microvascular disease, as seen in the retina, among participants who attended a population-based study in Australia (n=3654, aged 49+years).

METHODS

Diameters of retinal arterioles and venules were measured from digitised photographs of each participant to obtain an estimate of generalised arteriolar narrowing. Focal arteriolar narrowing, arteriovenous nicking, and retinopathy lesions (microaneurysms, haemorrhages, hard/soft exudates) were graded using a standard protocol. Fasting blood tests were performed in 89% of subjects. Adjusted means were calculated using general linear models. Logistic regression models were used to determine the odds ratios for retinal microvascular signs.

RESULTS

After controlling for age, sex, body mass index, smoking, and mean arterial blood pressure, elevated high-density lipoprotein cholesterol was associated with narrower retinal arterioles (Ptrend=0.002) and venules (Ptrend=0.03) and with increased odds of generalised arteriolar narrowing (odds ratio 1.6, 95% confidence interval 1.1-2.2 for the highest vs the lowest quintile of high-density lipoprotein cholesterol). Serum triglyceride had a U-shaped relationship with venular diameter (Ptrend=0.003). We found no consistent pattern of association between serum total cholesterol or low-density lipoprotein cholesterol and any retinal microvascular signs.

CONCLUSIONS

These findings suggest that microvascular disease in the retina may result from processes distinct from dyslipidaemia.

Age-related maculopathy and cataract surgery outcomes: visual acuity and health-related quality of life

PURPOSE

To assess visual acuity (VA) and health-related quality of life (HRQoL) outcomes in patients with and without age-related maculopathy (ARM) after cataract surgery.

METHODS

Patients aged 60+ years who had undergone cataract surgery at the Westmead Hospital during 2001-2003 were re-examined 1-3 years after surgery. Tests included VA and assessment of visual- and HRQoL using standardised questionnaires (VF-14, SF-12). Preoperative comorbidity data were collected from medical records. Poor surgical outcomes (VA<6/12; no VA improvement; lowest quintile of VF-14, SF-12 scores) were compared in patients with and without ARM, adjusting for age, sex, preoperative systemic comorbidities, ocular comorbidities and surgical or postoperative complications.

RESULTS

Of 622 surviving patients, 454 (73%) were followed up for a mean period of 2.8 years. Similar proportions with VA>or=6/12 were observed in patients with (80.2%) and without (88.8%) pre-existing ARM. Preoperative early ARM was only associated with slightly lower mean VF-14 scores (87.64 with vs 92.58 without ARM, P=0.01). Increasing age and preoperative ocular comorbidities were associated with all poor outcomes measured. Low SF-12 scores were associated with preoperative systemic comorbidities.

CONCLUSION

Our study documents favourable cataract surgical outcomes 1-3 years after cataract surgery in patients with preoperative ARM.

Temporal changes in the control of blood pressure in an older Australian population

Trends in blood pressure prevalence and control have important public health implications. We aim to document trends in hypertension prevalence, awareness and control in the older Australian population, a group at greatest risk of blood pressure related diseases. The Blue Mountains Eye Study (BMES) is a population-based study of residents aged 49 years or older, in two postcode areas of the Blue Mountains, Australia. The first cross-section (BMES I, 1992-1994) included 3654 participants (82.4% of eligible). The second cross-section (BMES II, 1997-2000) included 3509 participants, 2335 (75.1% of BMES I survivors) and 1174 (85.2% of newly eligible residents who qualified because of age or moved into the area). Detailed history and examinations were conducted. The prevalence of hypertension increased significantly from 45.4% (95% confidence interval, CI 43.7-47.0%) to 52.2% (CI 50.6-53.9%) from 1992-1994 to 1997-2000, paralleled by an increase in the population mean body mass index (BMI) from 26.1 kg/m2 (CI 26.0-26.3 kg/m2) to 27.7 kg/m2 (CI 27.5-27.9 kg/m2). Hypertension awareness decreased significantly from 79.8 to 73.0%, while treatment and control rates decreased from 71.1 to 67.3% and 56.3 to 46.5%, respectively (P<0.0001). Our results showed that elevated BMI (P<0.0001), lack of exercise (P<0.002) and serum triglyceride >2 mmol/l (P<0.0001) were significantly associated with prevalence of hypertension. We found that the prevalence of hypertension in the older Australian population was increasing while awareness, treatment and control rates decreased. Programmes to improve community awareness of hypertension, and its association with BMI may lead to further reductions in blood pressure and the burden of cardiovascular disease.

Five-year change in visual acuity following cataract surgery in an older community: the Blue Mountains Eye Study

AIMS

To assess the change in visual acuity following cataract surgery in the Blue Mountains Eye Study (BMES) population. Change in visual acuity was assessed by age, sex, baseline cataract type, and baseline visual acuity.

METHODS

A 5-year prospective follow-up of the population-based BMES cohort, who were initially examined in 1992. After 5 years, 2335 survivors of 3654 (75.1%) baseline BMES participants were re-examined. Slit-lamp and retro-illumination lens photographs were graded for the presence of incident cataract and evidence of cataract surgery. Visual acuity was measured using a logMAR chart, read at 2.4 m. The main outcome measure was change in the number of logMAR letters correctly identified by eyes that underwent cataract surgery during the 5-year follow-up period.

RESULTS

In a multiple linear regression model, age (P<0.0001) and early age-related maculopathy (ARM) at baseline (P<0.0001) were found to affect adversely the postoperative visual acuity following the cataract surgery. As expected, eyes with any baseline cataract showed the greatest improvement in visual acuity after cataract surgery (right eyes: mean +/- s.e. change of 3.75 +/- 1.34 letters; left eyes: mean change +/- s.e. of 6.7 +/- 0.99 letters). There was also a statistically significant improvement in vision after cataract surgery in eyes with no significant lens opacity graded as present at baseline (right eyes: mean +/- s.e. change of 3.78 +/- 1.85 letters; left eyes: mean change +/- s.e. of 2.68 +/- 1.33 letters).

CONCLUSIONS

Age and baseline cataract or ARM status, and baseline visual acuity were determinants of the postoperative visual outcome in older persons who underwent cataract surgery in this community.

Retinal vessel wall signs and the 5 year incidence of age related maculopathy: the Blue Mountains Eye Study

AIMS

To assess whether retinal arteriolar wall changes (focal narrowing and arteriovenous nicking) are associated with an increased 5 year risk of age related maculopathy (ARM).

METHODS

The Blue Mountains Eye Study examined 3654 residents aged 49+ years living in a defined area, during 1992-4 (82.4% participation). After 5 years, 2335 surviving participants (75.1%) were re-examined during 1997-9. Retinal photographs were graded using the Wisconsin ARM grading system. Incident late (neovascular or atrophic) or early stage ARM was defined using a side by side grading method. Focal arteriolar narrowing (localised constricted arteriolar segments causing a sausage-like appearance), and arteriovenous (AV) nicking (constriction on both sides of the venule where crossed by an arteriole), were graded by comparison with standard photographs. All retinal vessels passing through a circumferential zone 0.5-1.0 disc diameters from the optic disc margin were measured from digitised images. Summarised estimates for central retinal arteriolar equivalent (CRAE) represent an average diameter of arterioles for that eye. Associations were assessed after adjusting for age, sex, smoking, mean arterial blood pressure, and other vascular risk factors.

RESULTS

Of 2314 baseline participants at risk of late stage ARM, either late stage lesion developed in 34 participants (1.5%). Of 2203 at risk of early stage ARM, this sign developed in 197 participants (8.9%). Focal arteriolar narrowing was present at baseline in at least one eye of 162 survivors (6.9%) and severe AV nicking was present in 187 people (8.1%). Over 5 years, 4.9% of subjects with and 1.2% of those without focal narrowing developed either late stage ARM lesion, age adjusted relative risk (RR) 2.3, 95% confidence interval (CI) 1.0 to 5.1, multivariate adjusted odds ratios (OR) 2.1 (95% CI 0.9 to 4.9). Similarly, 3.7% of subjects with and 1.3% of those without severe AV nicking developed late ARM lesions, age adjusted RR 2.1 (95% CI 0.9 to 5.1), multivariate adjusted OR 2.2 (95% CI 0.9 to 5.6). Corresponding age adjusted RR and multivariate adjusted OR for development of early stage ARM were 1.4 (95% CI 0.9 to 2.0) and 1.3 (95% CI 0.8 to 2.1) for focal arteriolar narrowing, and 1.6 (95% CI 1.0 to 2.3) and 1.8 (95% CI 1.1 to 2.9) for severe AV nicking, respectively. No associations between baseline CRAE and 5 year incident late or early stage ARM were found.

CONCLUSIONS

Although of borderline statistical significance, the consistent associations found in this study suggest that structural retinal arteriolar changes may either contribute to ARM progression or may share common pathological pathways with ARM.

Female reproductive factors and open angle glaucoma: the Blue Mountains Eye Study

AIMS

To determine whether endogenous oestrogen exposures are associated with open angle glaucoma (OAG).

METHODS

The Blue Mountains Eye Study examined 2072 women aged 49-97 years during 1992-4. Questions about female reproductive factors included age at menarche and menopause, parity, and use of hormone replacement therapy. Applanation tonometry, visual field tests, and stereo-optic disc photographs were performed. OAG was diagnosed when glaucomatous visual fields matched optic disc changes. Ocular hypertension (OH) was defined in the absence of glaucoma, but with intraocular pressure >or=22 mm Hg.

RESULTS

A significantly increased OAG risk with later (>13 years) compared with earlier (<or=12 years) age of menarche was found, odds ratio (OR) = 2.0; 95% confidence interval (CI) 1.0 to 3.9, p for trend = 0.01, after adjustment for multiple confounders. Non-significant increased odds for OAG were found for early natural menopause (<45 years) compared with the reference group (>or=50 years), adjusted OR = 1.7; CI: 0.7 to 3.8, and for shorter duration of endogenous oestrogen exposure (<30 years), adjusted OR = 1.8; CI: 0.6 to 5.3. Increasing parity was associated with an increased risk of OAG (p = 0.03) and decreased risk of OH (p = 0.03).

CONCLUSION

The modest associations found in relation to late menarche and increased parity do not allow the exclusion of a possible role for endogenous female hormones in the pathogenesis of OAG.

Open-angle glaucoma and systemic thyroid disease in an older population: The Blue Mountains Eye Study

PURPOSE

To assess whether thyroid disease is independently associated with open-angle glaucoma (OAG), using history of thyroid disease and current thyroxine use.

METHODS

The Blue Mountains Eye Study examined 3654 persons, aged 49-97 years. Interviewers collected self-reported history of diagnosis and treatment for thyroid disease. Eye examinations included applanation tonometry, stereoscopic optic disc photography and automated perimetry. OAG was diagnosed from the presence of matching typical glaucomatous field changes and optic disc cupping, independent of intraocular pressure. Associations between thyroid disease (history and treatment) and OAG were assessed in a multivariate model.

RESULTS

Of 324 participants (8.9%) reporting history of thyroid disease, 147 (4.0%) were currently using thyroxine. Although we could not accurately categorize the thyroid disorder for all cases, current use of thyroxine suggests a prior hypothyroid state. All thyroid disease subgroups affected women more frequently than men, P=0.001. OAG was diagnosed in 108 subjects (3.0%) and was more frequent in those reporting past thyroid disease (4.6 vs 2.8%). This relationship was not statistically significant after adjusting for potential confounders, multivariate odds ratio (OR) 1.6; 95% confidence interval (95% CI) 0.9-2.9. OAG was significantly more frequent, however, in subjects reporting current thyroxine use (6.8 vs 2.8%), multivariate OR 2.1; 95% CI 1.0-4.4, or history of thyroid surgery (6.5 vs 2.8%), multivariate OR 2.5; 95% CI 1.0-6.2.

CONCLUSIONS

This population-based study suggests that thyroid disease, indicated by current thyroxine use or past thyroid surgery, could be independently related to OAG.

Unilateral visual impairment and health related quality of life: the Blue Mountains Eye Study

BACKGROUND

There has been considerable recent interest in the impact of unilateral visual impairment on functional status and wellbeing, particularly in relation to second eye cataract surgery.

AIM

To determine if unilateral visual impairment has a measurable impact on health related quality of life (HRQOL) in an older community, as assessed by the generic, multidimensional 36 item short form health survey (SF-36).

METHODS

All participants of the second cross sectional Blue Mountains Eye Study (n = 3508) were invited to attend comprehensive eye examinations and complete an SF-36 questionnaire. Unilateral visual impairment was defined as visual acuity (VA) <6/12 in the worse eye and > or =6/12 in the better eye. Mild visual impairment was defined as VA <6/12 but > or =6/24, moderate as VA <6/24 but > or =6/60, and severe (blindness) as VA <6/60 in the worse eye. Cases with amblyopia (n = 48) were excluded.

RESULTS

Complete data were available for 3108 participants; 227 (7.3%) had unilateral visual impairment (148 mild, 29 moderate, 50 severe). Moderate to severe non-correctable unilateral impairment was associated with poorer SF-36 profiles. After adjusting for age and sex, this group had significantly poorer scores than the unimpaired group in three of eight domains (p<0.05); limitations as a result of physical problems, social function, limitations because of emotional problems, and in the mental component score. Mental domains were more affected than physical domains. Unilateral impairment from undercorrected refraction did not measurably affect HRQOL.

CONCLUSIONS

Moderate to severe non-correctable unilateral visual impairment caused by eye diseases such as cataract had a measurable impact on HRQOL.

Five year incidence of cataract surgery: the Blue Mountains Eye Study

AIMS

To assess the 5 year incidence of cataract surgery in an older population based prospective cohort.

METHODS

5 Year prospective follow up of the population based Blue Mountains Eye Study (BMES) performed in 1992. The follow up study examined 2335 survivors (75.1%) of the 3654 baseline participants. Baseline and 5 year slit lamp and retroillumination lens photographs were graded for presence of cortical, nuclear, or posterior subcapsular cataract using the Wisconsin cataract grading method and cataract surgery was documented from the history and the clinical examination.

RESULTS

An overall cataract surgery rate of 5.7% in first or both eyes was documented. The incidence was 0.3% in people aged 49-54 years at baseline, 1.7% for ages 55-64 years, 7.9% for ages 65 to 74 years, and 17.4% in people aged 75 years or older. The rate of surgery in first or both eyes was 6.0% in women and 5.2% in men, age adjusted p = 0.66. Bilateral cataract surgery was performed during follow up on 2.7% of participants, while 43.1% of unilateral phakic cases had second eye surgery. Presence of any posterior subcapsular (PSC) cataract, either alone or in combination with other cataract types, was the most likely type of cataract at baseline to be associated with incident cataract surgery. Baseline age was the most important non-ocular variable predicting incident cataract surgery.

CONCLUSIONS

This study has documented age specific rates for 5 year incident cataract surgery in an older community. The finding of relatively similar incidence rates and ocular predictors of cataract surgery to those reported by the Beaver Dam Eye Study, Wisconsin, United States, is of interest, given previous documented similarities between these two populations.

Prevalence and associations with ectropion in an older population: the Blue Mountains Eye Study

The aim of this study was to describe the prevalence of eyelid ectropion and its associations with sunlight-related and other ocular variables, plus systemic factors, in an older Australian population. The Blue Mountains Eye Study examined 3654 persons aged 49-97 years. Examination recorded ectropion and other ocular signs. The questionnaire assessed sunlight-related and systemic variables. Ectropion was present in either eye of 143 subjects (3.9%) and was bilateral in 101 (70.6%). A marked age-related increase in prevalence was observed with ectropion found in 0.3% of persons aged < 60 years, 1.2% of ages 60-69 years, 6.7% of ages 70-79 years and 16.7% of those aged 80 years or older Ectropion prevalence was higher in men (5.1%) than women (3.0%), age-adjusted odds ratio 2.1 (95% confidence interval 1.5-3.0). Statistically significant associations were found between ectropion and history of skin cancer removal, increased skin sun sensitivity, lighter iris colour and presence of pingueculum, as well as current smoking, hypertension, diabetes and stroke.

Lower nasal distribution of cortical cataract: the Blue Mountains Eye Study

Previous reports have indicated that cortical cataract commences in the lower nasal lens, possibly due to sunlight exposure because of the shallow brow temporally. The present study aimed to assess the lens sector distribution of cortcal cataract in a population. The Blue Mountains Eye Study assessed 3654 residents aged 49-97 years; 3270 phakic subjects had retroillumination lens photographs graded using the Wisconsin method, which divides the lens into eight radial sectors with a grid overlay. Graders estimated percentage of cortical opacity in each sector. The lower nasal area consistently had the greatest opacity, a pattern present at each age and similar in both sexes, despite the 20% greater cortical cataract in women. The mean area of lens cortex involved by opacities in the lower nasal hemisphere was four fold greater than in the upper temporal hemisphere at each age. The lower nasal distributon was highly symmetrical when both eyes were affected. When > 20% of the lower nasal lens quadrant had cortical opacity, 88% of bilaterally affected subjects had cortical cataract n the same quadrant of the fellow eye. The lower nasal distribution may indicate a role for sunlight in the aetiology of cortcal cataract, which could be considered when examining other cortical cataract risk factors, such as diabetes, vascular disease and hormonal factors in women.

Projected number of Australians with glaucoma in 2000 and 2030

Accurate Australian glaucoma prevalence has been provided by two population-based studies: the Blue Mountains Eye Study (BMES) and the Melbourne Visual Impairment Project (MVIP). Both stud es defined glaucoma as the presence of matching optic disc cupp ng with rim thinning and g aucomatous field defects demonstrated on automated perimetry Combining 'definite' and 'probable' rates, the glaucoma prevalence in persons aged 50 and over, age-standardized for the 2000 projected Australian population, was 2.70% (BMES) and 3.13% (MVIP), including rates for 'definite' glaucoma of 2.12% (BMES) and 2.50% (MVIP). The number of Australians aged 50 and over in the year 2000 with g aucoma could be estimated as from 144 000 persons (BMES) to 167 000 persons (MVIP). Assuming similar age-specific rates, the number of Austral ans aged 50 and over in the year 2030 wth glaucoma could be estimated as from 307 000 persons (BMES) to 337 000 persons (MVIP). Ocular hypertens on (OH) was defined as present in subjects without glaucoma wth intraocular pressure (IOP) of more than 21 mmHg, including treated subjects with 'normal' examination IOP The age-standardized OH prevalence was 5.15% (BMES), which projects to 275000 Australians with OH in 2000, increasing to 513000 in 2030.

Projected number of Australians with visual impairment in 2000 and 2030

This study aimed to project population-based prevalence data associated with visual impairment, in order to estimate the number of affected older Australians (aged 50 or older) in the years 2000 and 2030. We used data from the Blue Mountains Eye Study (BMES) and Melbourne Visual Impairment Project (MVIP), together with Australian Bureau of Statistics population projections. Similar definitions for moderate (6/24-6/60 visual acuity) and severe (< 6/60 visual acuity) visual impairment were used. Combining age-standardized data, we estimated that in the year 2000, 38 820 (0.73%) and 25590 (0.48%) Australians aged 50 years or older will have moderate and severe visual impairment, respectively. By 2030, these rates will have more than doubled, to an estimated 85910 (0.92%) and 57930 (0.62%) Australians with moderate and severe visual impairment, respectively. Women aged 50 years or older will have a 1.8-fold and four-fold risk, respectively, of moderate and severe visual impairment compared to men. Visual impairment will affect an increasing proportion of older Australians, Newer approaches to therapy, rehabilitation and community support for persons with visual impairment will be needed to meet this challenge.