Different combinations of glucose tolerance and blood pressure status and incident cardiovascular disease and all-cause mortality events

Body mass index and risk of all-cause mortality among elderly Chinese: An empirical cohort study based on CLHLS data

The aim of our study was to evaluate the relationship between body mass index (BMI) and all-cause mortality among elderly Chinese. The subjects of our study were a cohort of 13 319 elderly Chinese enrolled between 2008 and 2018. Participants were classified in three groups: underweight (<18.5 kg/m²), normal weight (18.5-24.9 kg/m²), overweight and obese (≥25 kg/m²) according to different BMI levels. Cox proportional-hazards regression model was used to analyze the association between BMI grouping and the risk of mortality among the three groups and each corresponding subgroup. The restricted cubic spline regression was performed to investigate the variation tendency of BMI and mortality in different groups and subgroups. We found that the hazard ratios (HRs) of mortality in the underweight and the normal-weight groups were 1.213 and 1.104, respectively, compared with those in the overweight and obesity groups. HR for mortality decreased as BMI increased, although this phenomenon was not observed as not a linear relationship in all participants. Nonetheless, this nonlinear relationship was significant in type 2 diabetes patients. Among subjects with non-type 2 diabetes, the shape of the negative curve, reflecting the HR for BMI and mortality, decreased when BMI increased. Our findings suggest that an obesity paradox exists in non-type 2 diabetes patients, in which BMI has a nonlinear negative relationship with mortality. Conversely, in type 2 diabetes patients there is a U-shaped association. Obesity may thus be protective for all-cause mortality among non-diabetic older populations.

Prediabetes and risk for all-cause and cardiovascular mortality based on hypertension status

Background

Current recommendations suggest prediabetes testing for overweight or obese adults with at least one cardiovascular risk factor. However, it is important to understand whether testing should be conducted in adults with hypertension regardless of their cardiovascular risk factors.

Methods

Participants from the 1999–2014 National Health and Nutrition Examination Surveys (NHANES) aged at least 18 years and without diabetes were enrolled in the study. Participants were classified according to their prediabetes and hypertension status and followed up to track cardiovascular and all-cause mortality until December 31, 2015. Cox proportional hazards models were built to estimate the hazard ratios (HRs). Results were stratified by age, sex, ethnicity, body mass index, and cardiovascular disease history.

Results

At baseline, 5,011 (14.72%) out of 34,047 participants had combined prediabetes and hypertension. Prediabetes alone was not associated with all-cause or cardiovascular mortality. Hypertension alone was significantly associated with all-cause (HR: 1.30) and cardiovascular (HR: 1.89) mortality, and combined prediabetes and hypertension were significantly associated with all-cause (HR: 1.37) and cardiovascular (HR: 2.11) mortality. Age and ethnicity were significantly associated with combined prediabetes and hypertension and all-cause mortality, where the association was stronger among people aged <60 years (HR: 1.94 vs. 1.22) and White (HR: 1.50 vs. 1.21).

Conclusions

Prediabetes might elevate the risk of all-cause and cardiovascular mortality among people with hypertension. This relationship is more evident among younger and White individuals.

Systolic Blood Pressure, Cardiovascular Mortality, and All-Cause Mortality in Normoglycemia, Prediabetes, and Diabetes

BACKGROUND

The optimal blood pressure (BP) level for diabetic patients remains controversial, while studies provided limited evidence on BP management for individuals with normoglycemia or prediabetes. We aimed to investigate the associations between systolic blood pressure (SBP) and all-cause and cardiovascular (CVD) mortality among US adults with different glycemic profiles.

METHODS

We used data from the 1999-2014 National Health and Nutrition Examination Survey (NHANES, n=40,046) with comprehensive baseline examination and follow-up assessment. Restricted cubic spline analysis was performed to examine dose-response relationship between SBP and mortality risk. Cox regression models were used to estimate hazard ratios of all-cause mortality and CVD mortality for SBP categories.

RESULTS

U-shaped associations between SBP and all-cause mortality were observed regardless of glucose status. The relationship between SBP and CVD mortality was found to be U-shaped only in normoglycemic participants. The lowest mortality risk of optimal SBP (mmHg) by group was 115-120 (normoglycemia), 120-130 (prediabetes), and 125-135 (diabetes). When compared with the reference group, SBP < 100 mmHg was significantly associated with 49% (HR=1.49, 95% CI: 1.13-1.96), 57% (1.57, 1.07-2.3), and 59% (1.59, 1.12-2.25) higher all-cause mortality risk in people with normoglycemia, prediabetes, and diabetes, respectively. The multivariable-adjusted HRs of all-cause mortality for SBP ≥150 mmHg were 1.51 (1.25-1.82), 1.56 (1.27-1.93), and 1.33 (1.08-1.64), respectively. As for CVD mortality, the multivariable-adjusted HRs were 2.85 (1.29-6.33) for SBP <100 mmHg and 2.71 (1.56-4.69) for SBP ≥150 mmHg in normoglycemia; HR was 1.66 (1.05-2.63) for SBP ≥150 mmHg in diabetic patients.

CONCLUSION

U-shaped relationships between SBP and all-cause mortality were observed regardless of diabetes status. The optimal SBP range was gradually higher with worsening glucose status.

Blood Pressure and Hypertension: Findings from 20 Years of the Tehran Lipid and Glucose Study (TLGS)

CONTEXT

Hypertension (HTN) is a well-known modifiable risk factor for cardiovascular disease (CVD), chronic kidney disease and mortality. Positive effects of blood pressure (BP) lowering for prevention of CVD and death have been documented in several meta-analyses of randomized controlled trials.

EVIDENCE ACQUISITION

This review focuses on the key findings derived from the Tehran lipid and glucose study (TLGS) papers on different aspects of BP and HTN.

RESULTS

A prevalence of 23% for HTN has been reported in the TLGS population, aged ≥ 20 years. Over a decade long follow-up, the crude incidence rate (95% CI) of new-onset HTN defined as systolic BP (SBP) ≥ 140 mmHg and/or diastolic BP (DBP) ≥ 90 mmHg, and not using antihypertensive medication was 33.63 (32.0 - 35.3) per 1000 person-years. Age, baseline SBP and body mass index were significant risk factors for development of isolated systolic HTN; regarding isolated diastolic HTN, baseline DBP and waist circumference were recognized as important risk factors whereas age, female gender and marriage were shown to be protective factors. SBP decreased significantly in both diabetic and non-diabetic participants; DBP showed a non-significant decrease in diabetic men and a statistically significant decrease in non-diabetic men. Among women, both those with and without diabetes (DM) generally experienced statistically significant decreases in DBP. Cox proportional hazard models showed that neither SBP nor DBP were associated with incident DM in the total population and in either gender, separately. All BP components were associated with CVD and all-cause mortality in the middle-aged population. Contribution of HTN to cerebrovascular events was also documented in the TLGS participants, aged ≥ 50 years.

CONCLUSIONS

Several important findings regarding BP/HTN have been derived from the TLGS. According to data regarding the prevalence and incidence of preHTN and HTN and their contribution to cardiovascular morbidity and mortality in the TLGS population as a representative sample of Tehranian population, it is recommended that interventions be prioritized for lifestyle modifications for the prevention and appropriate management of preHTN/HTN.