Kaisu Kaikkonen

Occupational and genetic risk factors associated with intervertebral disc disease

Study Design. Cross-sectional epidemiologic study. Objective. To evaluate the interaction between known genetic risk factors and whole-body vibration for symptomatic intervertebral disc disease (IDD) in an occupational sample. Summary of Background Data. Risk factors of IDD include, among others, whole-body vibration and heredity. In this study, the importance of a set of known genetic risk factors and whole-body vibration was evaluated in an occupational sample of train engineers and sedentary controls. Methods. Eleven variations in 8 genes (COL9A2, COL9A3, COL11A2, IL1A, IL1B, IL6, MMP-3, and VDR) were genotyped in 150 male train engineers with an average of 21-year exposure to whole-body vibration and 61 male paper mill workers with no exposure to vibration. Subjects were classified into IDD-phenotype and asymptomatic groups, based on the latent class analysis. Results. The number of individuals belonging to the IDD-phenotype was significantly higher among train engineers (42% of train engineers vs. 17.5% of sedentary workers; P = 0.005). IL1A −889T allele represented a significant risk factor for the IDD-phenotype both in the single marker allelic association test (P = 0.043) and in the logistic regression analysis (P = 0.01). None of the other allele markers was significantly associated with symptoms when analyzed independently. However, for all the SNP markers considered, whole-body vibration represents a nominally significant risk factor. Conclusion. The results suggest that whole-body vibration is a risk factor for symptomatic IDD. Moreover, whole-body vibration had an additive effect with genetic risk factors increasing the likelihood of belonging to the IDD-phenotype group. Of the independent genetic markers, IL1A −889T allele had strongest association with IDD-phenotype.

Are the determinants of vertebral endplate changes and severe disc degeneration in the lumbar spine the same? A magnetic resonance imaging study in middle-aged male workers

BackgroundModic changes are bone marrow lesions visible in magnetic resonance imaging (MRI), and they are assumed to be associated with symptomatic intervertebral disc disease, especially changes located at L5-S1. Only limited information exists about the determinants of Modic changes. The objective of this study was to evaluate the determinants of vertebral endplate (Modic) changes, and whether they are similar for Modic changes and severe disc degeneration focusing on L5-S1 level.Methods228 middle-aged male workers (159 train engineers and 69 sedentary factory workers) from northern Finland underwent sagittal T1- and T2-weighted MRI. Modic changes and disc degeneration were analyzed from the scans. The participants responded to a questionnaire including items of occupational history and lifestyle factors. Logistic regression analysis was used to evaluate the associations between selected determinants (age, lifetime exercise, weight-related factors, fat percentage, smoking, alcohol use, lifetime whole-body vibration) and Modic type I and II changes, and severe disc degeneration (= grade V on Pfirrmanns classification).ResultsThe prevalences of the Modic changes and severe disc degeneration were similar in the occupational groups. Age was significantly associated with all degenerative changes. In the age-adjusted analyses, only weight-related determinants (BMI, waist circumference) were associated with type II changes. Exposure to whole-body vibration, besides age, was the only significant determinant for severe disc degeneration. In the multivariate model, BMI was associated with type II changes at L5-S1 (OR 2.75 per one SD = 3 unit increment in BMI), and vibration exposure with severe disc degeneration at L5-S1 (OR 1.08 per one SD = 11-year increment in vibration exposure).ConclusionBesides age, weight-related factors seem important in the pathogenesis of Modic changes, whereas whole-body vibration was the only significant determinant of severe disc degeneration.

Factors associated with parental recognition of a child's overweight status - a cross sectional study

BackgroundVery few studies have evaluated the association between a childs lifestyle factors and their parents ability to recognise the overweight status of their offspring. The aim of this study was to analyze the factors associated with a parents ability to recognise their own offsprings overweight status.Methods125 overweight children out of all 1,278 school beginners in Northern Finland were enrolled.Weight and height were measured in health care clinics. Overweight status was defined by BMI according to internationally accepted criteria. A questionnaire to be filled in by parents was delivered by the school nurses. The parents were asked to evaluate their offsprings weight status. The childs eating habits and physical activity patterns were also enquired about. Factor groups of food and physical activity habits were formed by factor analysis. Binary logistic regression was performed using all variables associated with recognition of overweight status in univariate analyses. The significant risk factors in the final model are reported using odds ratios (ORs) and their 95% confidence intervals (CIs).ResultsFifty-seven percent (69/120) of the parents of the overweight children considered their child as normal weight. Childs BMI was positively associated with parental recognition of overweight (OR 3.59, CI 1.8 to 7.0). Overweight boys were less likely to be recognised than overweight girls (OR 0.14, CI 0.033 to 0.58). Childs healthy diet (OR 0.22, CI 0.091 to 0.54) and high physical activity (OR 0.29, CI 0.11 to 0.79) were inversely related to parental recognition of overweight status.ConclusionsChilds healthy eating habits and physical activity are inversely related to parental recognition of their offsprings overweight. These should be taken into account when planning prevention and treatment strategies for childhood obesity.

Muscular Fitness in Relation to Physical Activity and Television Viewing among Young Adults

PURPOSE To study how time spent in physical activity and that in television (TV) viewing are associated with muscular fitness among young adults. METHODS The study population consisted of a cross-sectional sample of 381 males and 493 females aged 19.1 yr (SD 0.3) from the Northern Finland Birth Cohort 1986. Muscular fitness was measured by trunk muscle strength tests (trunk extension, flexion, and rotation) and jumping height test. Time spent on moderate- to vigorous-intensity physical activity and on TV viewing was self-reported by a questionnaire. RESULTS The most physically active young adults performed significantly better in most trunk muscle strength tests and the jumping test than the least active subjects. The mean difference between the most and least active groups was at minimum 1.6 kg (95% confidence interval (CI) = -0.5 to 3.7) and at maximum 10.6 kg (95% CI = 4.7-16.5) for different trunk muscle strength tests and at minimum 4.4 cm (95% CI = 2.7-6.1) for the jumping height test. Males and females who watched TV for >or=2 h x d(-1) performed significantly worse in trunk extension and flexion tests and females also performed worse in the jumping test compared with those who watched TV <2 h x d(-1), independent of their physical activity level. The mean difference between low and high TV users was at minimum -3.8 kg (95% CI = -6.7 to -0.9) for trunk extension and flexion strength and -1.2 cm (95% CI = -2.0 to -0.4) for jumping height in females. CONCLUSIONS Among young adults, daily TV viewing for >or=2 h, irrespective of physical activity level, was associated with poorer muscular fitness.

Lifestyle intervention has a beneficial effect on eating behavior and long-term weight loss in obese adults

OBJECTIVE To investigate the change in eating behavior and the factors related with the change among successful dieters (maintained a weight loss of ≥5% of original weight). METHODS Obese adult subjects (21 male, 55 female) were randomized into three-year lifestyle intervention (n=59) and control groups (n=17). Eating behavior (cognitive restraint of eating, uncontrolled eating and emotional eating) was evaluated by the TFEQ-18 and motivation to lose weight and tolerance to problems by a separate questionnaire. Weight, height and body mass index were measured. RESULTS Weight decreased more in the intervention group than in the control group (5.0% vs 0.6%, p=0.027). Cognitive restraint increased twice as much in the intervention group compared to the control group (16.0 vs. 7.0, p=0.044). The increment in cognitive restraint was positively associated with weight loss and high baseline motivation and tolerance to problems. Cognitive restraint increased in both successful (n=27) and unsuccessful dieters (n=32), but only the successful dieters were able to decrease uncontrolled eating in the long term. CONCLUSIONS Our results showed that intensive lifestyle counseling improved cognitive restraint which was associated with enhanced weight loss among obese adults. Successful dieters also showed a long-term improvement of uncontrolled eating. Eating behavior should be evaluated and followed before and during lifestyle interventions in order to support the change, e.g. by finding methods to control eating at risk situations and strengthening motivation and tolerance to problems.

Physical Activity and Aerobic Fitness are Positively Associated With Heart Rate Variability in Obese Adults

BACKGROUND Autonomic nervous system (ANS) dysfunction and obesity are intrinsically related to each other. In normal-weight subjects physical activity (PA) and fitness are related to cardiovascular autonomic regulation, providing evidence that aerobic training may improve ANS functioning measured by heart rate variability (HRV). The goal of this study was to investigate the association between lifetime PA, aerobic fitness and HRV in obese adults. METHODS Participants included 107 (87 females) volunteers (mean age 44.5 years, median BMI 35.7) who completed health and lifestyle questionnaires and measurements of maximal aerobic performance, anthropometry and 24 h HRV. RESULTS In the multivariate linear regression analyses, lifetime physical activity explained 40% of the variance in normal R-R intervals (SDNN). Each 1-category increase in the activity index increased SDNN by 15.4 (P = .009) and 24% of the variance in natural logarithmic value of ultra-low frequency power (P = .050). High measured VO2max explained 45% of the variance in natural logarithmic value of high-frequency power (P = .009) and 25% of the variance in low frequency/high frequency ratio (P < .001). CONCLUSIONS Lifetime physical activity and aerobic fitness may reduce obesity-related health risks by improving the cardiac autonomic function measured by HRV in obese working-age subjects. This research supports the role of lifetime physical activity in weight management strategies and interventions to reduce obesity-related health risks.

Exercise capacity and mortality – a follow-up study of 3033 subjects referred to clinical exercise testing

Abstract Background: Exercise stress testing is used as a diagnostic and prognostic tool. We determined the prognostic significance of exercise test findings for cardiovascular (CVD) and all-cause mortality in men and women. Material and methods: 3033 subjects underwent a symptom-limited bicycle exercise test. Exercise capacity was defined as the mean of last four minutes of exercise workload. Results: During an average follow-up of 19 years, 186 (11.6%) CVD and 370 (20.6%) all-cause deaths in men and 57 (5.0%) CVD and 155 (12.5%) all-cause deaths in women occurred. Among exercise test variables (workload, ECG, BP, HR), exercise capacity was the strongest predictor of mortality. Low exercise capacity (1st quartile) was associated with a hazard ratio of 4.2 (95% CI: 1.7, 10.8) for CVD and 4.0 (95% CI: 2.5, 6.4) for all-cause mortality compared with high exercise capacity (4th quartile) among men and in women with a 5.4-fold (95% CI: 1.2, 24.0) risk for CVD and 2.3-fold (95% CI: 1.2, 4.3) risk for all-cause mortality, respectively. The relationship between other exercise test variables and mortality was much weaker. Conclusions: Among exercise test variables exercise capacity was the strongest predictor of CVD and all-cause mortality in both genders, and especially CVD deaths in women. Key Messages Exercise capacity was the most powerful predictor of CVD and all-cause mortality in both men and women. Low exercise capacity is a strong predictor of CVD death, especially among women.

Association between overweight and low back pain: a population-based prospective cohort study of adolescents.

Study Design. A prospective cohort study in adolescents aged 7 to 19 years. Objective. To evaluate whether persistent overweight increases the risk of low back pain (LBP) among adolescents. Summary of Background Data. Overweight and LBP are common health problems in adolescents. Their relationship is still controversial among adolescents, as well as among adults. Methods. The study population, the Oulu Back Study, was drawn from the Northern Finland Birth Cohort 1986. The final study sample included 1660 adolescents (56% females). The subcohort of 786 subjects (57% females) was used in the analysis of waist circumference. The association between the area under the curve of body mass index from 7 to 16 years, and from 16 to 18 years, and area under the curve of waist circumference from 16 to 19 years, and LBP during the past 6 months was evaluated separately for incident (reporting LBP at 18 or 19 yr but not at 16 yr) and persistent LBP (reporting LBP at 16 and 18 yr or 19 yr). Relative risks (RR) and their 95% confidence intervals (95% CI) were adjusted for smoking, leisure time physical activity, and family socioeconomic status at 16 years and stratified by sex. Results. Body mass index from 16 to 18 years among girls and body mass index from 7 to 16 years among boys predicted incident LBP at 18 years (girls: RR, 1.09; 95% CI, 1.01–1.18; boys: RR, 1.15; 95% CI, 1.00–1.32). Among boys, waist circumference from 16 to 19 years was also associated with incident LBP (RR, 1.16; 95% CI, 1.02–1.32). Overweight was not associated with persistent LBP. Conclusion. In this population-based cohort study, persistent overweight slightly increased the risk of incident LBP, but the time period during which overweight was related to incident LBP differed between sexes. Level of Evidence: 2

Exercise and Fitness Are Related to Peripheral Nervous System Function in Overweight Adults

PURPOSE This study examined the association between physical activity and fitness and peripheral nervous system (PNS) function in overweight and obese individuals. METHODS Forty nondiabetic overweight adults (mean +/- SD; age = 44 +/- 11 yr) were recruited for the study. Peroneal motor nerve and radial, sural, and medial plantar sensory nerve conductions were studied. Maximal oxygen uptake was measured in an incremental bicycle ergometer test. Physical activity was assessed by accelerometer and self-reporting. We analyzed the data using multiple stepwise linear regression models adjusted for age, height, and skin temperature. RESULTS VO2max predicted 17% of peroneal distal compound muscle action potential (CMAP) amplitude variation and 16% of peroneal proximal CMAP amplitude variation. Physical activity index at the age of 30 yr predicted 9% of peroneal motor nerve conduction velocity (NCV), 8% of peroneal F-wave maximum latency, 14% of medial plantar sensory latency, and 10% of medial plantar sensory NCV variation. CONCLUSIONS Physical activity and fitness are positively associated with PNS function and should be encouraged in overweight people.