Associations of Insulin and Insulin-Like Growth Factors with Physical Performance in Old Age in the Boyd Orr and Caerphilly Studies

Objective Insulin and the insulin-like growth factor (IGF) system regulate growth and are involved in determining muscle mass, strength and body composition. We hypothesised that IGF-I and IGF-II are associated with improved, and insulin with worse, physical performance in old age. Methods Physical performance was measured using the get-up and go timed walk and flamingo balance test at 63–86 years. We examined prospective associations of insulin, IGF-I, IGF-II and IGFBP-3 with physical performance in the UK-based Caerphilly Prospective Study (CaPS; n = 739 men); and cross-sectional insulin, IGF-I, IGF-II, IGFBP-2 and IGFBP-3 in the Boyd Orr cohort (n = 182 men, 223 women). Results In confounder-adjusted models, there was some evidence in CaPS that a standard deviation (SD) increase in IGF-I was associated with 1.5% faster get-up and go test times (95% CI: −0.2%, 3.2%; p = 0.08), but little association with poor balance, 19 years later. Coefficients in Boyd Orr were in the same direction as CaPS, but consistent with chance. Higher levels of insulin were weakly associated with worse physical performance (CaPS and Boyd Orr combined: get-up and go time = 1.3% slower per SD log-transformed insulin; 95% CI: 0.0%, 2.7%; p = 0.07; OR poor balance 1.13; 95% CI; 0.98, 1.29; p = 0.08), although associations were attenuated after controlling for body mass index (BMI) and co-morbidities. In Boyd Orr, a one SD increase in IGFBP-2 was associated with 2.6% slower get-up and go times (95% CI: 0.4%, 4.8% slower; p = 0.02), but this was only seen when controlling for BMI and co-morbidities. There was no consistent evidence of associations of IGF-II, or IGFBP-3 with physical performance. Conclusions There was some evidence that high IGF-I and low insulin levels in middle-age were associated with improved physical performance in old age, but estimates were imprecise. Larger cohorts are required to confirm or refute the findings

Glucoregulation has greater impact on cognitive performance than macro-vascular disease in men with type 2 diabetes: Data from the Caerphilly study

Objective: To compare vascular and glucose related mechanisms of type 2 diabetes on cognitive performance. Research design and methods: A cross-sectional observational study of type 2 diabetes defined by non insulin dependant self-report diabetes or fasting blood glucose ≤ 7.0 mmol/l of 2205 men eligible for the third phase of the Caerphilly Collaborative Heart Disease Study. Men were aged 55–69 years at time of testing. Tests of cognitive function included NART (crystallised IQ), AH4 (fluid IQ), verbal fluency (executive function) Cambridge Cognitive Examination (CAMCOG) and Mini Mental State Examination (MMSE) (global function), four choice serial reaction time (psychomotor function) and memory. Men with prior stroke were omitted from the analysis. Results: Men with diabetes showed cognitive deficits for verbal fluency, National Adult Reacting Test (NART) and AH4. Adjusting for vascular risk factors had minimal effect. Including blood glucose removed the deficit for verbal fluency and NART but the effect on AH4 score (−2.58; 95% CI: −5.0, −0.1, p = 0.039) was retained. More detailed analyses of AH4 score on men with diabetes showed a curvilinear relationship indicating that men with both low and high glucose levels had worse performance (AH4 = −66 + 80 loge glucose – 18 loge glucose2; 95% CI: −29, −6; p=0.002). Conclusions: These data identify a direct effect of glucose regulation on cognitive performance associated with diabetes in a population sample. These data suggest that an effect of glucose regulation on cognitive performance in diabetes is distinct from any effect of macro-vascular disease

Cognitive function in the Caerphilly study: associations with age, social class, education and mood

Baseline cognitive function was established for a study of pre-symptomatic cognitive decline in 1870 men from the general population aged 55-69 years as part of the third examination of the Caerphilly Study. Cognitive assessment included the AH4, a four choice serial reaction time task, a modified CAMCOG, MMSE, NART and various memory tests. Distributions and relationships with age, social class, education and mood at time of testing are presented for a younger population than has previously been available. Multiple linear regression showed cognitive function to be independently associated with all four factors. The age effect was equivalent to one half of a standard deviation (SD) in CRT and AH4 scores. Only the NART score was not associated with age, supporting the use of NART score as an estimate of pre-morbid IQ. The largest age adjusted differences between men with low and normal mood were for the AH4 (3 points, t = 5.6, p < 0.0001) and the CAMCOG (2 points, t = 5.8, p < 0.0001). The smallest age adjusted effect of mood was for the CRT (33 ms, t = 2.14, p = 0.32) and the MMSE (0.4 points, t = 2.97, p = 0.003). Age, mood and education adjusted social class effects were very large ranging between around 0.5 SD for the CRT, and 1.0 SD for the AH4 and NART, respectively. For educational status age, mood and social class adjusted differences were also substantial with tests for trend showing the largest differences for the NART (t = 12, p < 0.0001) and modified CAMCOG (t = 10.6, p < 0.0001) with the smallest differences for the CRT (t = 2.73, p = 0.006)

Getting the old guys back on track: Management of PPID

STUDY OBJECTIVES: To examine the cognitive function in a large, ongoing cohort study of older men, and to identify associations with social and lifestyle factors. DESIGN: A cross sectional study of cognitive function was conducted within the Caerphilly Prospective Study of Heart Disease and stroke. SETTING: The Caerphilly Study was originally set up in 1979-83 when the men were 45-59 years of age. Extensive data are available on a wide range of lifestyle and other factors of possible relevance to cognitive decline. Associations between some of these and cognitive function are reported. PARTICIPANTS: A representative sample of 1870 men aged 55-69 years. MAIN RESULTS: Age, social class, medication, and mood were found to be powerful determinants of performance. Self report data on the involvement of the men in leisure pursuits were examined by factor analysis. This indicated that the more intellectual leisure pursuits are the most strongly linked with performance. A measure of social contact showed a weak positive association with the test scores. Current cigarette smokers gave lower test cognitive function scores than either men who had never smoked, or ex-smokers. There was however no evidence of any gradient in function with the total lifetime consumption of tobacco. The disparity between these two data sets suggests that there had been prior selection of men who had originally started to smoke, but more particularly selection of those who later quit smoking. There was no significant association between alcohol consumption and cognitive function, though ex-drinkers had markedly lower test scores than either current drinkers or men who had never drunk alcohol. This seemed probably to be a consequence of an high prevalence of illness among the ex-drinkers. CONCLUSIONS: Age and social class show strong associations with cognitive function. Leisure persuits and social contact are also both positively associated. Neither tobacco smoking nor the drinking of alcohol seem to be associated with cognitive function, though there is evidence suggestive of self selection of both men who had never smoked and ex-smokers

Better than any pill - and no side effects! Healthy lifestyles, statins and aspirin

Behaviors which are associated with the preservation of health include nonsmoking, regular exercise, a low body weight, a healthy diet, and a low alcohol intake. Together, as a healthy lifestyle, these have been shown to be associated with marked protection against a wide range of diseases: diabetes, vascular disease, cancer, and dementia. On the other hand, the protection associated with statins and aspirin, the two most commonly used preventive drugs, is limited to vascular disease and, probably for aspirin, cancer. These are not alternative prophylactics and any two, or all three—a healthy lifestyle, a statin, and aspirin—can reasonably be taken together. Only a small proportion of the members of the community follow a healthy lifestyle. Yet a small increase in the uptake of the healthy behaviors throughout the community can be shown to have relatively large effects on the incidence of disease. There is therefore an urgent need for health promotion activities across the whole community to be greatly increased and for new challenging and encouraging strategies to be devised and tested

Healthy living and cancer: Evidence from UK Biobank

Context UK Biobank is a prospective study of half a million subjects, almost all aged 40–69 years, identified in 22 centres across the UK during 2006–2010. Objective A healthy lifestyle has been described as ‘better than any pill, and no side effects [5]. We therefore examined the relationships between healthy behaviours: low alcohol intake, non-smoking, healthy BMI, physical activity and a healthy diet, and the risk of all cancers, colon, breast and prostate cancers in a large dataset. Method Data on lifestyle behaviours were provided by 343,150 subjects, and height and weight were measured at recruitment. 14,285 subjects were diagnosed with cancer during a median of 5.1 years of follow-up. Results Compared with subjects who followed none or a single healthy behaviour, a healthy lifestyle based on all five behaviours was associated with a reduction of about one-third in incident cancer (hazard ratio [HR] 0.68; 95% confidence intervals [CI] 0.63–0.74). Colorectal cancer was reduced in subjects following the five behaviours by about one-quarter (HR 0.75; 95% CI 0.58–0.97), and breast cancer by about one-third (HR 0.65; 95% CI 0.52–0.83). The association between a healthy lifestyle and prostate cancer suggested a significant increase in risk, but this can be attributed to bias consequent on inequalities in the uptake of the prostate specific antigen screening test. Conclusions Taken together with reported reductions in diabetes, vascular disease and dementia, it is clearly important that every effort is taken to promote healthy lifestyles throughout the population, and it is pointed out that cancer and other screening clinics afford ‘teachable moments’ for the promotion of a healthy lifestyle.</p