Heikki O. Tikkanen

Asthma and increased bronchial responsiveness in elite athletes: Atopy and sport event as risk factors☆☆☆★★★

BACKGROUND High prevalence of bronchial hyperresponsiveness and asthma has been found in cross-country skiers. There is limited evidence that asthma and bronchial responsiveness would be common also in athletes with summer events. OBJECTIVES The objective of this study was to investigate occurrence of and risk factors for increased bronchial responsiveness and asthma in elite athletes with summer events and to compare their results with those of control subjects. METHODS Forty-nine speed and power athletes (mean age 21.1 years, range 16 to 31), 71 long-distance runners (mean age 26.6 years, range 16 to 39), 42 swimmers (mean age 18.6 years, range 14 to 25), and 45 control subjects (mean age 26.7 years, range 21 to 37) were studied. The subjects answered questionnaires and were given a resting spirometric examination, a skin prick test, and a histamine challenge test. RESULTS Current asthma (current asthmatic symptoms and increased bronchial responsiveness) was observed in 14% (22 of 162) of the athletes and in 2% (1 of 45) of the control subjects (p = 0.041). Total asthma (current asthmatic symptoms and increased bronchial responsiveness or physician-diagnosed asthma) occurred in 23% (37 of 162) of the athletes and in 4% (2 of 45) of the control subjects (p = 0.0048). Atopy according to skin prick test results was found in 48% (77 of 162) of the athletes and in 36% (16 of 45) of the control subjects (not significant). Clinical pollen allergy (positive skin test reaction to pollen and symptoms of rhinoconjunctivitis) was significantly (p = 0.037) more common in athletes than in control subjects. Atopic athletes showed significantly more often increased bronchial responsiveness, current asthma, and total asthma than nonatopic athletes (p = 0.011, p = 0.0049, and p < 0.0001, respectively), and the odds ratios of increased bronchial responsiveness and asthma increased with the number of positive skin test reactions. After adjustment for confounding factors, the odds ratio for the occurrence of current asthma was 5.49 (95% confidence interval 0.56 to 53.7) in speed and power athletes, 2.88 (0.30 to 27.7) in long-distance runners, and 10.8 (1.10 to 106.0) in swimmers compared with control subjects. The adjusted odds ratios for the occurrence of total asthma were 3.56 (0.62 to 20.5) in speed and power athletes, 6.01 (1.19 to 30.2) in long-distance runners, and 5.89 (1.00 to 34.5) in swimmers. CONCLUSIONS Asthma is more common in highly trained athletes than in control subjects. Asthma is especially common in elite swimmers, but the risk of asthma is increased also in long-distance runners. Increased bronchial responsiveness and asthma are strongly associated with atopic disposition and its severity in elite athletes.

New susceptibility loci associated with kidney disease in Type 1 diabetes

Diabetic kidney disease, or diabetic nephropathy (DN), is a major complication of diabetes and the leading cause of end-stage renal disease (ESRD) that requires dialysis treatment or kidney transplantation. In addition to the decrease in the quality of life, DN accounts for a large proportion of the excess mortality associated with type 1 diabetes (T1D). Whereas the degree of glycemia plays a pivotal role in DN, a subset of individuals with poorly controlled T1D do not develop DN. Furthermore, strong familial aggregation supports genetic susceptibility to DN. However, the genes and the molecular mechanisms behind the disease remain poorly understood, and current therapeutic strategies rarely result in reversal of DN. In the GEnetics of Nephropathy: an International Effort (GENIE) consortium, we have undertaken a meta-analysis of genome-wide association studies (GWAS) of T1D DN comprising ∼2.4 million single nucleotide polymorphisms (SNPs) imputed in 6,691 individuals. After additional genotyping of 41 top ranked SNPs representing 24 independent signals in 5,873 individuals, combined meta-analysis revealed association of two SNPs with ESRD: rs7583877 in the AFF3 gene (P = 1.2×10−8) and an intergenic SNP on chromosome 15q26 between the genes RGMA and MCTP2, rs12437854 (P = 2.0×10−9). Functional data suggest that AFF3 influences renal tubule fibrosis via the transforming growth factor-beta (TGF-β1) pathway. The strongest association with DN as a primary phenotype was seen for an intronic SNP in the ERBB4 gene (rs7588550, P = 2.1×10−7), a gene with type 2 diabetes DN differential expression and in the same intron as a variant with cis-eQTL expression of ERBB4. All these detected associations represent new signals in the pathogenesis of DN.

Occurrence of exercise induced bronchospasm in elite runners: dependence on atopy and exposure to cold air and pollen.

OBJECTIVES: To study factors affecting the occurrence of exercise induced bronchospasm (EIB) in elite runners. METHODS: Fifty eight elite runners, 79% of them belonging to Finnish national teams, volunteered. The athletes answered a questionnaire on respiratory symptoms. Skin prick tests were used to investigate atopy, and spirometry to examine lung function at rest and after an exercise challenge test (ECT) at subzero temperature in the winter and after a similar ECT in the summer at the end of the birch pollen season. RESULTS: Definitive EIB (a post-exercise reduction of 10% or more in forced expiratory volume in one second (FEV1) was observed in five (9%) of the 58 runners. A subgroup consisting of 19 non-atopic symptom-free runners with no family history of asthma was used to establish a normal range for post-exercise reduction in FEV1. When this groups mean exercise induced change in FEV1 minus 2 SDs (a reduction of 6.5% or more in FEV1) was taken as the lower limit of the reference range, 15 (26%) of the runners had probable EIB in either the winter or the pollen season. The occurrence of probable EIB depended on atopy (odds ratio increased with number of positive skin prick test reactions, p < 0.05). Nine (22%) of the 41 runners, challenged in both the winter and the pollen season, had probable EIB only in the winter, and three (7%) had it only in the pollen season. Only one runner (2%) had EIB in both tests. CONCLUSIONS: Mild EIB is common in Finnish elite runners and is strongly associated with atopy. Seasonal variability affects the occurrence of EIB, and thus exercise testing should be performed in both cold winter air and the pollen season to detect EIB in elite runners.

Life events and change in leisure time physical activity: a systematic review.

The global epidemic of chronic non-communicable diseases is closely related to changes in lifestyle, including decreasing leisure time physical activity (PA). Physical inactivity is a major public health challenge. To respond to that challenge, it is essential to know which personal and environmental factors affect PA behaviour. Certain life events may be one contributing factor, by creating emotional distress and disrupting a person’s daily routine.The aim was to examine the literature concerning the effects of life events on changes in PA. A systematic literature search was performed on studies that assessed at least one major change in life circumstances and a change in PA. To be included, studies had to assess PA at two timepoints at least (before and after the event). Diseases as life events were excluded from this review. Thirty-four articles met the inclusion criteria. The studies examined the following life-change events: transition to university; change in employment status; marital transitions and changes in relationships; pregnancy/having a child; experiencing harassment at work, violence or disaster; and moving into an institution.The studies reviewed showed statistically significant changes in leisure PA associated with certain life events. In men and women, transition to university, having a child, remarriage and mass urban disaster decreased PA levels, while retirement increased PA. In young women, beginning work, changing work conditions, changing from being single to cohabiting, getting married, pregnancy, divorce/separation and reduced income decreased PA. In contrast, starting a new personal relationship, returning to study and harassment at work increased PA. In middle-aged women, changing work conditions, reduced income, personal achievement and death of a spouse/partner increased PA, while experiencing violence and a family member being arrested or jailed decreased PA. In older women, moving into an institution and interpersonal loss decreased PA, while longer-term widowhood increased PA. In addition, experiencing multiple simultaneous life events decreased PA in men and women.Major life events have a strong effect on leisure PA behaviour. Consequently, people experiencing life events could be an important target group for PA promotion. More research is needed to examine the short- and longterm effects of different life events on PA, gender differences in the effects of life events and the specific determinants of PA change during life events.

Occurrence of chronic disease in former top-level athletes. Predominance of benefits, risks or selection effects?

Former elite athletes from most sports disciplines have lower overall morbidity risk and enjoy better self-rated health in later years compared with the general population and matched controls who were healthy at young age. This is seen particularly among former endurance athletes who have a lower incidence of coronary heart disease and type 2 diabetes mellitus. Most often data are available only for men. Based on the available data, participation in elite sports cannot be regarded as an overall health hazard. However, aside from a high risk of acute injury in specific sports, possible negative effects of long-standing athletic activity on the development of osteoarthritis should not be neglected. It should also be remembered that elite athletes are a biologically and genetically select group who are not representative of the population at large. Given the nature of the available data, the possible health consequences of recent changes in different characteristics of sports, such as training practices, professionalism and use of doping, cannot be properly predicted.

Physical Activity and Diabetes Complications in Patients With Type 1 Diabetes: The Finnish Diabetic Nephropathy (FinnDiane) Study

Physical activity exerts numerous beneficial health effects, and the evidence favoring a physically active lifestyle in the treatment of chronic diseases is substantial (1). For patients with diabetes, physical activity is considered important (2). In theory, regular physical activity may prevent diabetes complications through beneficial effects on glycemic control, insulin sensitivity, blood pressure, lipid profile, and endothelial function. However, physical activity could also cause adverse effects or patients may not be able to exercise due to complications. Little, however, is known about the relationship between physical activity and diabetes complications (3). Therefore, we investigated the associations between physical activity and microvascular and macrovascular diabetic complications in a large cohort of patients with type 1 diabetes from the Finnish Diabetic Nephropathy (FinnDiane) Study. The FinnDiane Study and the assessment of self-reported leisure-time physical activity (LTPA) by a questionnaire have previously been described (4). This is a cross-sectional analysis of 1,945 patients with data on LTPA. Renal status was based on at least three urine collections. Renal function was evaluated by the Cockcroft-Gault formula (5) for estimated creatinine clearance. Data on retinopathy and cardiovascular disease (CVD) were obtained from medical records. Differences between groups were …

Prediction of Acute Mountain Sickness by Monitoring Arterial Oxygen Saturation During Ascent

Acute mountain sickness (AMS) is a common problem while ascending at high altitude. AMS may progress rapidly to fatal results if the acclimatization process fails or symptoms are neglected and the ascent continues. Extensively reduced arterial oxygen saturation at rest (R-Spo₂) has been proposed as an indicator of inadequate acclimatization and impending AMS. We hypothesized that climbers less likely to develop AMS on further ascent would have higher Spo₂ immediately after exercise (Ex-Spo₂) at high altitudes than their counterparts and that these postexercise measurements would provide additional value for resting measurements to plan safe ascent. The study was conducted during eight expeditions with 83 ascents. We measured R-Spo₂ and Ex-Spo₂ after moderate daily exercise [50 m walking, target heart rate (HR) 150 bpm] at altitudes of 2400 to 5300 m during ascent. The Lake Louise Questionnaire was used in the diagnosis of AMS. Ex-Spo₂ was lower at all altitudes among those climbers suffering from AMS during the expeditions than among those climbers who did not get AMS at any altitude during the expeditions. Reduced R-Spo₂ and Ex-Spo₂ measured at altitudes of 3500 and 4300 m seem to predict impending AMS at altitudes of 4300 m (p < 0.05 and p < 0.01) and 5300 m (both p < 0.01). Elevated resting HR did not predict impending AMS at these altitudes. Better aerobic capacity, younger age, and higher body mass index (BMI) were also associated with AMS (all p < 0.01). In conclusion, those climbers who successfully maintain their oxygen saturation at rest, especially during exercise, most likely do not develop AMS. The results suggest that daily evaluation of Spo₂ during ascent both at rest and during exercise can help to identify a population that does well at altitude.

Prevalence of Acute Mountain Sickness among Finnish Trekkers on Mount Kilimanjaro, Tanzania: An Observational Study

The aim of this study was to evaluate the prevalence of acute mountain sickness (AMS) among trekkers on Mount Kilimanjaro during the winter season of 2006-2007. A A total of 130 Finnish trekkers at Marungu route were asked to complete daily a Lake Louise self-report and clinical assessment score questionnaire with the help of a trainee Finnish guide during their trek to Kilimanjaro. A Lake Louise questionnaire score>or=3 indicated AMS. Altogether 112 mountaineers or travelers [54 men, 58 women, mean age 51+/-10 (SD) years] were studied. Fifty-nine travelers (53%) reached Gillmans Point or Uhuru Peak. The incidence of AMS among Finnish Kilimanjaro trekkers was 75%. The most common high altitude symptoms were headache, followed by sleeping problems and fatigue or weakness. The incidence of AMS is high among trekkers climbing Mount Kilimanjaro.The main reason for this seems to be rapid ascent. Kilimanjaro treks normally have a fixed timetable, and for commercial reasons there is little opportunity to spend extra days for acclimatization in the camps. Some contributing factors are preventable, so we recommend an educational program for all the trekking agencies that guide on this peak and, in particular, the Tanzania-based guiding agencies, which, typically, are driving these very fast ascent rates.

Physical Activity and Diabetic Complications in Patients With Type 1 Diabetes (The FinnDiane Study).

Physical activity exerts numerous beneficial health effects, and the evidence favoring a physically active lifestyle in the treatment of chronic diseases is substantial (1). For patients with diabetes, physical activity is considered important (2). In theory, regular physical activity may prevent diabetes complications through beneficial effects on glycemic control, insulin sensitivity, blood pressure, lipid profile, and endothelial function. However, physical activity could also cause adverse effects or patients may not be able to exercise due to complications. Little, however, is known about the relationship between physical activity and diabetes complications (3). Therefore, we investigated the associations between physical activity and microvascular and macrovascular diabetic complications in a large cohort of patients with type 1 diabetes from the Finnish Diabetic Nephropathy (FinnDiane) Study. The FinnDiane Study and the assessment of self-reported leisure-time physical activity (LTPA) by a questionnaire have previously been described (4). This is a cross-sectional analysis of 1,945 patients with data on LTPA. Renal status was based on at least three urine collections. Renal function was evaluated by the Cockcroft-Gault formula (5) for estimated creatinine clearance. Data on retinopathy and cardiovascular disease (CVD) were obtained from medical records. Differences between groups were …

Natural selection to sports, later physical activity habits, and coronary heart disease

Objectives—To investigate the associations between natural selection to sports at a young age, continuity of physical activity, and occurrence of coronary heart disease. Design—Prospective cohort study. Setting—Finland. Participants—Former top level male athletes participating at a young age (1920–1965) in different types of sport (endurance (n = 166), power speed (n = 235), “other” (n = 834)) and controls healthy at the age of 20 years (n = 743). Main outcome measures—Data on the occurrence of coronary heart disease were obtained from death certificates, three nationwide registers, and questionnaire studies in 1985 and 1995, and data on later physical activity were obtained from the questionnaires. Results—In 1985 all groups of former athletes were more physically active than controls (p<0.001). Despite similar total volumes of physical activity, compared with power speed athletes, former endurance athletes participated more often in vigorous activity (p = 0.006) and had less coronary heart disease (adjusted odds ratio 0.34, 95% confidence interval 0.17 to 0.73; p = 0.004). In 1985 and 1995, both endurance and other athletes had less coronary heart disease than controls. From 1986 to 1995, the incidence of new coronary heart disease was lower among those who participated in vigorous physical activity in 1985. Conclusions—Both a previous aptitude for endurance athletic events and continuity of vigorous physical activity seem to be associated with protection against coronary heart disease, but an aptitude for power speed events does not give protection against coronary heart disease.