Higher Fitness Is Strongly Protective in Patients with Family History of Heart Disease: The FIT Project

BACKGROUND

Cardiorespiratory fitness protects against mortality; however, little is known about the benefits of improved fitness in individuals with a family history of coronary heart disease. We studied the association between cardiorespiratory fitness and risk of incident coronary heart disease and all-cause mortality, hypothesizing an inverse relationship similar to individuals without a family history of coronary heart disease.

METHODS

We included 57,999 patients (aged 53 ± 13 years; 49% were female; 29% were black) from the Henry Ford Exercise Testing (FIT) Project. Cardiorespiratory fitness was expressed in metabolic equivalents of task based on exercise stress testing. Family history was determined as self-reported coronary heart disease in a first-degree relative at any age. We used Cox proportional hazards models adjusted for demographics and cardiovascular disease risk factors to examine the association between cardiorespiratory fitness and risk of incident coronary heart disease and mortality over a median (interquartile range) follow-up of 5.5 (5.6) and 10.4 (6.8) years, respectively.

RESULTS

Overall, 51% reported a positive family history. Each 1-unit metabolic equivalent increase was associated with lower incident coronary heart disease and mortality risk regardless of family history status. The hazard ratio and 95% confidence interval for a negative family history and a positive family history were 0.87 (0.84-0.89) and 0.87 (0.85-0.89) for incident coronary heart disease and 0.83 (0.82-0.84) and 0.83 (0.82-0.85) for mortality, respectively. There was no significant interaction between family history and categoric cardiorespiratory fitness, sex, or age (P >.05 for all).

CONCLUSIONS

Higher cardiorespiratory fitness is strongly protective in all patients regardless of family history status, supporting recommendations for regular exercise in those with a family history.

High Exercise Capacity Attenuates the Risk of Early Mortality After a First Myocardial Infarction: The Henry Ford Exercise Testing (FIT) Project

OBJECTIVE

To examine the effect of objectively measured exercise capacity (EC) on early mortality (EM) after a first myocardial infarction (MI).

PATIENTS AND METHODS

This retrospective cohort study included 2061 patients without a history of MI (mean age, 62±12 years; 38% [n=790] women; 56% [n=1153] white) who underwent clinical treadmill stress testing in the Henry Ford Health System from January 1, 1991, through May 31, 2009, and suffered MI during follow-up (MI event proportion, 3.4%; mean time from the exercise test to MI, 6.1±4.3 years). Exercise capacity was categorized on the basis of peak metabolic equivalents (METs) achieved: less than 6, 6 to 9, 10 to 11, and 12 or more METs. Early mortality was defined as all-cause mortality within 28, 90, or 365 days of MI. Multivariable logistic regression models were used to assess the effect of EC on the risk of mortality at each time point post-MI adjusting for baseline demographic characteristics, cardiovascular risk factors, medication use, indication for stress testing, and year of MI.

RESULTS

The 28-day EM rate was 10.6% overall, and 13.9%, 10.7%, 6.9%, and 6.0% in the less than 6, 6 to 9, 10 to 11, and 12 or more METs categories, respectively (P<.001). Patients who died were more likely to be older, be less fit, be nonobese, have treated hypertension, and have a longer duration from baseline to incident MI (P<.05). Adjusted regression analyses revealed a decreased risk of EM with increasing EC categories. A 1-MET higher EC was associated with an 8% to 10% lower risk of mortality across all time points (28 days: odds ratio [OR], 0.92; 95% CI, 0.87-0.98; P=.006; 90 days: OR, 0.90; 95% CI, 0.86-0.95; P<.001; 365 days: OR, 0.91; 95% CI, 0.87-0.94; P<.001).

CONCLUSION

Higher baseline EC was independently associated with a lower risk of early death after a first MI.

Cardiorespiratory fitness attenuates risk for major adverse cardiac events in hyperlipidemic men and women independent of statin therapy: The Henry Ford ExercIse Testing Project

AIMS

We sought to evaluate the effect of cardiorespiratory fitness (CRF) in predicting mortality, myocardial infarction (MI), and revascularization in patients with hyperlipidemia after stratification by gender and statin therapy.

METHODS AND RESULTS

This retrospective cohort study included 33,204 patients with hyperlipidemia (57 ± 12 years old, 56% men, 25% black) who underwent physician-referred treadmill stress testing at the Henry Ford Health System from 1991 to 2009. Patients were stratified by gender, baseline statin therapy, and estimated metabolic equivalents from stress testing. We computed hazard ratios using Cox regression models after adjusting for demographics, cardiac risk factors, comorbidities, pertinent medications, interaction terms, and indication for stress testing.

RESULTS

There were 4,851 deaths, 1,962 MIs, and 2,686 revascularizations over a median follow-up of 10.3 years. In men and women not on statin therapy and men and women on statin therapy, each 1-metabolic equivalent increment in CRF was associated with hazard ratios of 0.86 (95% CI 0.85-0.88), 0.83 (95% CI 0.81-0.85), 0.85 (95% CI 0.83-0.87), and 0.84 (95% CI 0.81-0.87) for mortality; 0.93 (95% CI 0.90-0.96), 0.87 (95% CI 0.83-0.91), 0.89 (95% CI 0.86-0.92), and 0.90 (95% CI 0.86-0.95) for MI; and 0.91 (95% CI 0.88-0.93), 0.87 (95% CI 0.83-0.91), 0.89 (95% CI 0.87-0.92), and 0.90 (95% CI 0.86-0.94) for revascularization, respectively. No significant interactions were observed between CRF and statin therapy (P > .23).

CONCLUSION

Higher CRF attenuated risk for mortality, MI, and revascularization independent of gender and statin therapy in patients with hyperlipidemia. These results reinforce the prognostic value of CRF and support greater promotion of CRF in this patient population.

Prognostic value of exercise capacity in patients with coronary artery disease: the FIT (Henry Ford ExercIse Testing) project

OBJECTIVE

To examine the prognostic value of exercise capacity in patients with nonrevascularized and revascularized coronary artery disease (CAD) seen in routine clinical practice.

PATIENTS AND METHODS

We analyzed 9852 adults with known CAD (mean ± SD age, 61±12 years; 69% men [n=6836], 31% black race [n=3005]) from The Henry Ford ExercIse Testing (FIT) Project, a retrospective cohort study of patients who underwent physician-referred stress testing at a single health care system between January 1, 1991, and May 31, 2009. Patients were categorized by revascularization status (nonrevascularized, percutaneous coronary intervention [PCI], or coronary artery bypass graft [CABG] surgery) and by metabolic equivalents (METs) achieved on stress testing. Using Cox regression models, hazard ratios for mortality, myocardial infarction (MI), and downstream revascularizations were calculated after adjusting for potential confounders, including cardiac risk factors, pertinent medications, and stress testing indication.

RESULTS

There were 3824 all-cause deaths during median follow-up of 11.5 years. In addition, 1880 MIs, and 1930 revascularizations were ascertained. Each 1-MET increment in exercise capacity was associated with a hazard ratio (95% CI) of 0.87 (0.85-0.89), 0.87 (0.85-0.90), and 0.86 (0.84-0.89) for mortality; 0.98 (0.96-1.01), 0.88 (0.84-0.92), and 0.93 (0.90-0.97) for MI; and 0.94 (0.92-0.96), 0.91 (0.88-0.95), and 0.96 (0.92-0.99) for downstream revascularizations in the nonrevascularized, PCI, and CABG groups, respectively. In each MET category, the nonrevascularized group had similar mortality risk as and higher MI and downstream revascularization risk than the PCI and CABG surgery groups (P<.05).

CONCLUSION

Exercise capacity was a strong predictor of mortality, MI, and downstream revascularizations in this cohort. Furthermore, patients with similar exercise capacities had an equivalent mortality risk, irrespective of baseline revascularization status.

Vav2 protein overexpression marks and may predict the aggressive subtype of ductal carcinoma in situ

Background

A subset of patients with ductal carcinoma in situ (DCIS) will develop invasive breast cancer (IBC). To date, there are no effective predictive biomarkers for identifying this subset with worse prognosis whose lesions are essentially indistinguishable histologically from those with favorable outcomes. We hypothesized that measurable parameters that discriminate DCIS from DCIS with concurrent invasion may serve as diagnostic biomarkers (BM) of progressive cancer in situ (CIS).

Results

Using a novel imaging-based method of tissue testing, we measured the relative expression levels of three candidate BM proteins specifically implicated in IBC progression - the insulin-like growth factor I receptor (IGF-IR), Ras-related protein 1 (Rap1), and Vav2 oncoprotein. Protein profiles were compared in 42 histologically normal mammary epithelial samples, 71 CIS (35 without/36 with invasion either on diagnostic biopsy or final surgical excision), and 98 IBC of known estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) status. The levels of the IGF-IR and Rap1 protein expression were significantly elevated in ER-positive (ER+/PR+/-/HER2 –) DCIS relative to normal epithelium (P <0.0001). The IGF-IR protein expression was also significantly up regulated in HER2-positive (ER+/-/PR+/-/HER2+) DCIS relative to normal epithelium (P = 0.0002). IGF-IR and Rap1 protein expression levels were similar among DCIS patients without or with concurrent invasion. Vav2 upregulation in DCIS relative to normal group was not associated with steroid hormone receptor and HER2 status, but was associated with the presence of concurrent invasion, including microinvasion (invasive foci of less than 1 mm). DCIS with high Vav2 were more than twice as likely to progress to invasive cancers as DCIS with low Vav2 (odds ratio, 2.42; 95% CI, 1.26-4-65; P =0.008). Furthermore, a receiver operating characteristic curve analysis revealed moderate ability of Vav2 protein expression measurements in DCIS to predict the existence of invasion concurrent with DCIS (area under the curve, 0.71; 95% CI, 0.59- 0.84).

Conclusions

Our novel findings hold promise for utilizing Vav2 protein as a predictive BM for differentiating progressive from non-progressive DCIS.

Electronic supplementary material

The online version of this article (doi:10.1186/2050-7771-2-22) contains supplementary material, which is available to authorized users.

Colorectal neoplasia: performance characteristics of CT colonography for detection in 300 patients

PURPOSE

To determine the sensitivity and specificity of computed tomographic (CT) colonography for colorectal polyp and cancer detection by using colonoscopy as the reference standard.

MATERIALS AND METHODS

Three hundred patients underwent CT colonography followed by standard colonoscopy. Bowel preparation consisted of magnesium citrate and polyethylene glycol. After colonic air insufflation, patients underwent scanning in the supine and prone positions with 3-mm collimation during a single breath hold. The transverse CT images, sagittal and coronal reformations, and three-dimensional endoluminal images were interpreted by two radiologists independently, and then a consensus reading was performed. CT colonographic findings were correlated with standard colonoscopic and histologic findings.

RESULTS

The overall sensitivity and specificity of CT colonography for polyp detection were 90.1% (164 of 182) and 72.0% (85 of 118), respectively. By using direct polyp matching, the overall sensitivity was 69.7% (365 of 524). The sensitivity was 90% (74 of 82) for the detection of polyps 10 mm or larger, 80.1% (113 of 141) for polyps 5.0-9.9 mm, and 59.1% (178 of 301) for polyps smaller than 5 mm. The sensitivity was 94% (64 of 68) for the detection of adenomas 10 mm or larger, 82% (72 of 88) for adenomas 5.0-9.9 mm, and 66.9% (95 of 142) for adenomas smaller than 5 mm. CT colonography was used to identify all eight carcinomas.

CONCLUSION

CT colonography has excellent sensitivity for the detection of clinically important colorectal polyps and cancer.

The usefulness of glucagon hydrochloride for colonic distention in CT colonography

OBJECTIVE

The purpose of this study was to compare colonic distention with and without glucagon hydrochloride during CT colonography.

SUBJECTS AND METHODS

CT colonography using single breath-hold, thin-section helical technique was performed on 60 patients who were in the supine and prone positions. Magnesium citrate and polyethylene glycol were used for bowel preparation. Colonic air insufflation averaged 30 bulb compressions. Thirty-three patients received IV glucagon (1 mg), and 27 patients did not. The colon was divided into eight segments, and the adequacy of the distention of each segment was evaluated. Overall colonic distention scores, defined as the number of inadequately distended segments (0-8), were recorded for the supine, prone, and combined positions. In the combined position, inadequate distention was defined as identical segments that were inadequately distended in both positions.

RESULTS

A total of 960 segments were evaluated: 528 segments in the glucagon group and 432 segments in the nonglucagon group. In the glucagon group, 444 segments (84.1%) were adequately distended. In the nonglucagon group, 365 segments (84.5%) were adequately distended. The median and range for overall colonic distention scores in the supine, prone, and combined positions were 1 (0-3), 1 (0-3), and 0 (0), respectively, for the glucagon group and 1 (0-6), 1 (0-6), and 0 (0-1), respectively, for the nonglucagon group. We found no statistically significant difference in overall colonic distention between the glucagon group and the nonglucagon group for the supine (p = .84), prone (p = .15), or combined (p = .28) positions.

CONCLUSION

Glucagon administration before CT colonography does not improve colonic distention.

Static load response of the heels of SACH feet

Excessive heel hardness in the prosthetic foot is a frequent problem that may contribute to decreased function in the above knee and below knee amputee. Optimal mechanical characteristics of the SACH (solid ankle cushion heel) foot have not been defined. In an effort to characterize the mechanical properties of the heels of these feet, we performed static load-deformation tests on the heels of SACH feet at stimulated heelstrike. These data were interpreted using least squares fitting of the natural logarithms of the load-deformation data. Statistical comparison of these data revealed no significant difference in the static response of the "medium" and "regular" grades of foot. A difference at the 1% level of confidence was found between the "soft" grade and the two firmer grades. Consistency within a grade of foot was quite good. Comparison of feet from another manufacturer revealed no difference in static response, suggesting consistency in static performance among manufactures. It was our clinical impression that all grades of SACH heels are too stiff.