Adipose Tissue,Muscle, and Function: Potential Mediators of Associations Between Body Weight and Mortality in Older Adults With Type 2 Diabetes

OBJECTIVEStudies in type 2 diabetes report both increased mortality for normal weight and no evidence of an obesity paradox. We aimed to examine whether adipose tissue, muscle size, and physical function, which are known to vary by weight, mediate associations between BMI and mortality.RESULTSThe median follow-up was 6.66 years, and there were 85, 59, and 44 deaths among normal weight, overweight, and obese participants, respectively. There was no mortality risk for obese participants and an increased risk among normal weight compared with overweight participants (HR 1.72 [95% CI 1.12–2.64]). Associations remained with adjustment for adipose tissues and knee extensor strength; however, mortality risk for normal weight was attenuated following adjustment for thigh muscle (HR 1.36 [95% CI 0.87–2.11]) and gait speed (HR 1.44 [95% CI 0.91–2.27]). Linear regression confirmed with bootstrapping indicated that thigh muscle size mediated 46% of the relationship between normal weight and mortality.CONCLUSIONSNormal weight participants had elevated mortality risk compared with overweight participants. This paradoxical association was mediated in part by muscle size.     

The Cross-sectional and Longitudinal Associations of Diabetic Retinopathy With Cognitive Function and Brain MRI Findings: The Action to Control Cardiovascular Risk in Diabetes (ACCORD) Trial

OBJECTIVELongitudinal evidence linking diabetic retinopathy with changes in brain structure and cognition is sparse. We used data from the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial to determine whether diabetic retinopathy at baseline predicted changes in brain structure or cognition 40 months later.RESULTSBaseline retinopathy was associated with lower gray matter volume (adjusted means of 470, 466, and 461 cm³ for none, mild, and moderate/severe retinopathy, respectively; P = 0.03). Baseline retinopathy also predicted a greater change in MMSE and DSST scores at 40 months in each retinopathy category (MMSE: −0.20, −0.57, and −0.42, respectively [P = 0.04]; DSST: −1.30, −1.84, and −2.89, respectively[P = 0.01]).CONCLUSIONSDiabetic retinopathy is associated with future cognitive decline in people with type 2 diabetes. Although diabetic retinopathy is not a perfect proxy for diabetes-related brain and cognitive decline, patients with type 2 diabetes and retinopathy represent a subgroup at higher risk for future cognitive decline.     

Subclinical atherosclerotic calcification and cognitive functioning in middle-aged adults: The CARDIA study

Objective

Cardiovascular risk factors in middle-age are associated with cognitive impairment and dementia in older age. Less is known about the burden of calcified subclinical atherosclerosis and cognition, especially in midlife. We examined the association of coronary artery and abdominal aortic calcified plaque (CAC and AAC, respectively) with cognitive functioning in middle-aged adults.

Methods

This cross-sectional study included 2510 black and white adults (age: 43–55 years) without heart disease or stroke who completed a year 25 follow-up exam (2010–11) as part of the Coronary Artery Risk Development in Young Adults Study. CAC and AAC were measured with non-contrast computed tomography. Cognition was assessed with the Digit Symbol Substitution Test (DSST) (psychomotor speed), Stroop Test (executive function), and Rey Auditory Verbal Learning Test (RAVLT) (verbal memory).

Results

A greater amount of CAC and AAC was associated with worse performance on each test of cognitive function after adjustment for age, sex, race, education, and study center. Associations were attenuated, but remained significant for the DSST and RAVLT following additional adjustment for vascular risk factors, including adiposity, smoking, alcohol use, dyslipidemia, hypertension, and diabetes. Compared to participants without CAC or AAC, those with both CAC and AAC, but not CAC or AAC alone was associated with lower DSST scores (p < 0.05).

Conclusions

In this community-based sample, greater subclinical atherosclerotic calcification was associated with worse psychomotor speed and memory in midlife. These findings underscore the importance of a life course approach to the study of cognitive impairment with aging.     

The healthy urinary microbiome in asymptomatic participants in the MAPP Network Study: Relation to gender,age, and menopausal status

IntroductionTo understand the role of the urinary microbiome in disease states and interpret non-culture-based diagnostic urine testing of midstream urine specimens, we must have a better understanding of the urinary microbiome in asymptomatic, healthy individuals. We examined the impact of gender, age, and menopausal status on the healthy human urinary microbiome in asymptomatic control subjects enrolled in the multi-institution National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) Multidisciplinary Approach to the Study of Chronic Pelvic Pain Network (MAPP) study.MethodsAsymptomatic, healthy controls, recruited to be ageand sex-matched to patients in the Trans-MAPP Epidemiology and Phenotyping Study, provided midstream urine collection for polymerase chain reaction (PCR)-electrospray ionization mass spectrometry identification of urinary microbiota. The microbiomes of male and female participants were described and analyzed for differences in composition and diversity at the species and genus level by sex, age, and, in females, by menopausal status.ResultsSixty-six total species were detected with a mean of 1.2 species (standard deviation [SD] 1.1) per male (n=97; mean age=43) and 2.3 (SD 1.3) per female (n=110, mean age=38) in asymptomatic, healthy controls. Species and genera diversity analyses showed significantly greater richness and diversity in females. With regard to species, Bifidobacterium subtile, Lactobacillus crispatus, and Lactobacillus johnsonii were more predominant in females. The genera Bifidobacterium, Staphylococcus, Lactobacillus, and Corynebacterium were more predominant in females, while for males the most prevalent organisms included Staphylococcus and Propionibacterium; only Propionibacterium approached a significant difference between genders. No significant difference in the presence and/or diversity of micro-organisms with menopausal status could be observed. Sex-specific age trends, particularly diversity, were larger for females than males.ConclusionsThese results suggest the urinary microbiome of healthy, asymptomatic subjects differed between genders and age in females, but not menopausal status. Gender differences may be attributable to the detection of urethral/vaginal organisms in females and prostate organisms in males. These findings will better allow us to interpret the results of microbiome reports in the midstream urine specimens of patients with urinary symptoms.     

Co-factors affecting substance abuse among homosexual men: an investigation within a midwestern gay community

In an effort to begin formation of an empirically based model of gay substance abuse, this study examined the effects of three psychosocial factors, homosexual identity formation, self-esteem and a familial history of substance abuse in the evolution of this phenomenon among homosexual men, a group that appears to manifest appreciably higher rates and concomitantly greater associated problems than the general population. Data were obtained by voluntary subject return of a self-report instrument that was distributed widely over a 6 month period in the metropolitan Cleveland area, resulting in a moderately sized sample. Although the sampling method limited the generalizibility of the results, diminished self-esteem and a familial history of substance abuse had significant associations with both alcohol and drug abuse and were confirmed to be salient predictors, together accounting for almost half the variance in alcohol abuse and over one-third the variance in drug abuse. Moreover, both had the ability to significantly discern between alcohol and drug use groups versus groups found to be alcohol and drug abusive. Levels of a gay identity were not meaningfully associated with substance abuse. Finally, recommendations for further research were explicated.     

Alcohol septal ablation after failed surgical myectomy.

We describe the case of a successful alcohol septal ablation in a patient with persistent gradient and severe symptoms postsurgical myectomy. The alcohol ablation of the thickened septum abolished the left ventricular outflow gradient and the systolic anterior motion (SAM) of the mitral valve. Although the surgical literature advocates for mitral valve replacement in patients who continue to have SAM with significant outflow obstruction postmyectomy, targeted alcohol septal ablation of the remaining septum appears to be an attractive alternative.