Overview of recruitment for the osteoporotic fractures in men study (MrOS).

Large, long term research studies present recruitment challenges that can be met with collaborative approaches to identify and enroll participants. The Osteoporotic Fractures in Men Study (MrOS), a multi-center observational study designed to determine risk factors for osteoporosis, fractures and prostate cancer in older men, recruited 5995 participants over a 25-month period. Enrolling a cohort that represented the race and age distribution of each community, and developing interest in an older male cohort about a condition commonly thought of as a "women's disease," were major recruitment challenges. During the start-up phase, recruitment challenges and strategies were analyzed and collective approaches were developed to address ways to motivate the target population. Key methods included mailings using community and provider contact lists; regional and senior newspaper advertisements; and presentations targeted to seniors. Sites used a centrally developed recruitment brochure. Response to mass mailings at some sites surpassed 10-15% and appointment show rates averaged above 85%. The final number enrolled in MrOS was 5% more than the original recruitment goal of 5700. Minority recruitment was enhanced through the use of the Health Care Financing Administration and other databases that allowed for targeted recruitment. Overall, minority enrollment was approximately 10.56% of the cohort (244 African American, 191 Asian). Men age>80 were enthusiastic and represent about 18% of enrollees. Through a coordinated approach of developing and refining recruitment strategies and materials, sites were able to adapt their original strategies and complete recruitment ahead of schedule.

Mortality risk in older men associated with changes in weight, lean mass, and fat mass.

OBJECTIVES: To evaluate risk of all-cause mortality associated with changes in body weight, total lean mass, and total fat mass in older men. DESIGN: Longitudinal cohort study. SETTING: Six U.S. clinical centers. PARTICIPANTS: Four thousand three hundred thirty-one ambulatory men aged 65 to 93 at baseline. MEASUREMENTS: Repeated measurements of body weight and total lean and fat mass were taken using dual-energy X-ray absorptiometry 4.6 ± 0.4 years apart. Percentage changes in these measures were categorized as gain (+5%), loss (-5%), or stable (-5% to +5%). Deaths were verified centrally according to death certificate reviews, and proportional hazard models were used to estimate the risk of mortality. RESULTS: After accounting for baseline lifestyle factors and medical conditions, a higher risk of mortality was found for men with weight loss (hazard rat (HR)=1.84, 95% confidence interval (CI)=1.50-2.26), total lean mass loss (HR=1.78, 95% CI=1.45-2.19), and total fat mass loss (HR=1.72, 95% CI=1.34-2.20) than for men who were stable for each body composition measure. Men with total fat mass gain had a slightly greater mortality risk (HR=1.29, 95% CI=0.99-1.67) than those who remained stable. These associations did not differ according to baseline age, obesity, or self-reported health status (P for interactions >.10), although self-reported weight loss intent altered mortality risks with total fat mass (P for interaction=.04) and total lean mass (P for interaction=.09) change. CONCLUSION: Older men who lost weight, total lean mass, or total fat mass had a higher risk of mortality than men who remained stable.

Insulin sensitizers may attenuate lean mass loss in older men with diabetes.

OBJECTIVE: To examine longitudinal changes in total and appendicular lean body mass in older men with impaired fasting glucose (IFG) or diabetes and to determine whether these changes differ by diabetes treatment. RESEARCH DESIGN AND METHODS: A total of 3,752 ambulatory men aged ≥ 65 years at baseline participated in a multicenter longitudinal cohort study. Baseline glycemic status was categorized as normoglycemia, IFG, undiagnosed/untreated diabetes, or treated diabetes. Insulin sensitizer medication use (metformin and/or thiazolidinediones) was assessed by prescription medication inventory. The change in total lean and appendicular lean mass was derived from dual X-ray absorptiometry scans taken at baseline and 3.5 ± 0.7 years later. RESULTS: This male cohort included 1,853 individuals with normoglycemia, 1,403 with IFG, 234 with untreated diabetes, 151 with diabetes treated with insulin sensitizers, and 111 with diabetes treated without insulin sensitizers. Men with untreated diabetes, diabetes treated without insulin sensitizers, or IFG had greater percentage loss in total or appendicular lean mass (P ≤ 0.05 in comparison to normoglycemic men). There remained a significantly greater percentage loss in appendicular lean mass for these groups even after adjustment for medical comorbidities or lifestyle factors. In contrast, the percentage loss in total or appendicular lean mass in men with diabetes treated with insulin sensitizers was significantly less than that in normoglycemic men in minimally and fully adjusted models. CONCLUSIONS: Skeletal muscle loss was accelerated in men with IFG and diabetes, except when the latter was treated with insulin sensitizers. These findings suggest that insulin sensitizers may attenuate muscle loss.

Metabolic syndrome and physical performance in elderly men: the osteoporotic fractures in men study.

OBJECTIVES: To examine the association between metabolic syndrome (MetS) and objective measures of physical performance. DESIGN: Cross-sectional analysis of the cohort study, the Osteoporotic Fractures in Men Study. SETTING: Six clinical sites in the United States. PARTICIPANTS: Five thousand four hundred fifty-seven ambulatory men (mean age 73.6 ± 5.9). MEASUREMENTS: Physical performance assessed according to grip strength, narrow walk speed, walking speed, and time to complete five repeated chair stands. Individual scores were converted to quintiles (worst=1 to best=5; unable to complete=0) and summed for an overall score (mean 11.6 ± 4.3, range, 1-20). MetS was defined according to World Health Organization criteria that include evidence of glucose dysregulation (insulin resistance, diabetes mellitus, or hyperinsulinemia) and at least two additional characteristics: high blood pressure, low high-density lipoprotein cholesterol, high triglycerides, obesity. RESULTS: More than one-quarter (26.3%) of participants met criteria for MetS. In separate linear regression models, four of five MetS components were related to performance (P<.001); only high blood pressure was unrelated. Men with MetS had a 1.1-point lower performance score (mean 10.8, 95% confidence interval (CI)=10.6-11.0) than men without MetS (mean 11.9, 95% CI=11.8-12.0) (P<.001), adjusting for age, race, education, and site. With further covariate adjustment, this difference was reduced but remained significant (ß=-0.78, P<.001). A graded association was observed between number of MetS components (0, 1, 2, or ≥3) and performance (P for trend <.001). Findings were similar excluding men with diabetes mellitus or obese men. CONCLUSION: Metabolic dysregulation is related to objectively assessed poorer physical performance in relatively healthy older men.

Association between insulin resistance and lean mass loss and fat mass gain in older men without diabetes mellitus.

OBJECTIVES: To examine the associations between insulin resistance and changes in body composition in older men without diabetes mellitus. DESIGN: Longitudinal cohort study of older men participating in the Osteoporotic Fractures in Men (MrOS) study. SETTING: Six U.S. clinical centers. PARTICIPANTS: Three thousand one hundred thirty-two ambulatory men aged 65 and older at baseline. MEASUREMENTS: Baseline insulin resistance was calculated for men without diabetes mellitus using the homeostasis model assessment of insulin resistance (HOMA-IR). Total lean, appendicular lean, total fat, and truncal fat mass were measured using dual energy X-ray absorptiometry scans at baseline and 4.6 ± 0.3 years later in 3,132 men with HOMA-IR measurements. RESULTS: There was greater loss of weight, total lean mass, and appendicular lean mass and less gain in total fat mass and truncal fat mass with increasing quartiles of HOMA-IR (P<.001 for trend). Insulin-resistant men in the highest quartile had higher odds of 5% or more loss of weight (odds ratio (OR)=1.88, 95% confidence interval (CI)=1.46-2.43), total lean mass (OR=2.09, 95% CI=1.60-2.73) and appendicular lean mass (OR=1.57, 95% CI=1.27-1.95) and lower odds of 5% or more gain in total fat mass (OR=0.56, 95% CI=0.45-0.68) and truncal fat mass (OR=0.52, 95% CI=0.42-0.64) than those in the lowest quartile. These findings remained significant after accounting for age, site, baseline weight, physical activity, and change in physical activity. These associations were also independent of other metabolic syndrome features and medications. CONCLUSION: Greater lean mass loss and lower fat mass gain occurred in insulin-resistant men without diabetes mellitus than in insulin-sensitive men. Insulin resistance may accelerate age-related sarcopenia.

Do muscle mass, muscle density, strength, and physical function similarly influence risk of hospitalization in older adults?

OBJECTIVES: To examine the association between strength, function, lean mass, muscle density, and risk of hospitalization. DESIGN: Prospective cohort study. SETTING: Two U.S. clinical centers. PARTICIPANTS: Adults aged 70 to 80 (N=3,011) from the Health, Aging and Body Composition Study. MEASUREMENTS: Measurements were of grip strength, knee extension strength, lean mass, walking speed, and chair stand pace. Thigh computed tomography scans assessed muscle area and density (a proxy for muscle fat infiltration). Hospitalizations were confirmed by local review of medical records. Negative binomial regression models estimated incident rate ratios (IRRs) of hospitalization for race- and sex-specific quartiles of each muscle and function parameter separately. Multivariate models adjusted for age, body mass index, health status, and coexisting medical conditions. RESULTS: During an average 4.7 years of follow-up, 1,678 (55.7%) participants experienced one or more hospitalizations. Participants in the lowest quartile of muscle density were more likely to be subsequently hospitalized (multivariate IRR=1.47, 95% confidence interval (CI)=1.24-1.73) than those in the highest quartile. Similarly, participants with the weakest grip strength were at greater risk of hospitalization (multivariate IRR=1.52, 95% CI=1.30-1.78, Q1 vs. Q4). Comparable results were seen for knee strength, walking pace, and chair stands pace. Lean mass and muscle area were not associated with risk of hospitalization. CONCLUSION: Weak strength, poor function, and low muscle density, but not muscle size or lean mass, were associated with greater risk of hospitalization. Interventions to reduce the disease burden associated with sarcopenia should focus on increasing muscle strength and improving physical function rather than simply increasing lean mass.

Physical performance and risk of hip fractures in older men.

The aim of these analyses was to describe the association between physical performance and risk of hip fractures in older men. Performance on five physical function exams (leg power, grip strength, usual walking pace, narrow walk balance test, and five repeated chair stands) was assessed in 5902 men >or=65 yr of age. Performance (time to complete or strength) was analyzed as quartiles, with an additional category for unable to complete the measure, in proportional hazards models. Follow-up averaged 5.3 yr; 77 incident hip fractures were confirmed by physician review of radiology reports. Poor physical performance was associated with an increased risk of hip fracture. In particular, repeated chair stand performance was strongly related to hip fracture risk. Men unable to complete this exam were much more likely to experience a hip fracture than men in the fastest quartile of this test (multivariate hazard ratio [MHR]: 8.15; 95% CI: 2.65, 25.03). Men with the worst performance (weakest/slowest quartile or unable) on at least three exams had an increased risk of hip fracture compared with men with higher functioning (MHR: 3.14, 95% CI: 1.46, 6.73). Nearly two thirds of the hip fractures (N = 49, 64%) occurred in men with poor performance on at least three exams. Poor physical function is independently associated with an increased risk of hip fracture in older men. The repeated chair stands exam should be considered in clinical settings for evaluation of hip fracture risk. Concurrent poor performance on multiple physical function exams is associated with an increased risk of hip fractures.

Prevalence of symptoms of cervical and lumbar stenosis among participants in the Osteoporotic Fractures in Men Study.

STUDY DESIGN: Cross-sectional. OBJECTIVES: To determine the prevalence of symptoms typical of cervical and lumbar stenosis, evaluate the relationship between lumbar and cervical symptoms, and assess the impact of these symptoms on health status. SUMMARY OF BACKGROUND DATA: Degenerative changes of the spine frequently associated with aging, may result in stenosis, a narrowing of the spinal canal. Little is known about the prevalence or health impact of symptoms associated with stenosis in older individuals. METHODS: Between March 2000 and April 2002, 5995 men aged > or = 65 years participating in the Osteoporotic Fractures in Men Study completed a self-administered questionnaire and clinical examination. Information was collected on demographics, spinal/joint health, and general health status. RESULTS: Overall, 14.4% of men had had clinically relevant neck pain during the previous year, and almost half this group (6.5%) had numbness/tingling/weakness (NTW) extending into the arm; 26.2% reported clinically relevant lower back pain, which in 12.2%, was accompanied by NTW extending into the leg. Men with spinal pain (neck or lower back) accompanied by NTW radiating into a limb had poorer health status than those with milder pain. CONCLUSIONS: Symptoms suggestive of cervical and lumbar stenosis are relatively common among this cohort of older men, and generalized spinal stenosis may occur in as many as 4%.