The association between self-reported symptoms of recent airway infection and CRP values in a general population

Association between serum 25-hydroxyvitamin D concentration and symptoms of respiratory tract infection in a Norwegian population: the Tromsø Study

OBJECTIVE

Previous studies have suggested anti-infection effects of vitamin D, although the associations reported between vitamin D (serum 25-hydroxyvitamin D (25(OH)D) concentration) and respiratory tract infection (RTI) are conflicting. The main aim of the present study was to explore this association in a Norwegian population.

DESIGN

We examined the association between serum 25(OH)D and recent RTI symptoms in 6350 middle-aged and elderly participants in the Tromsø Study 6. The main outcome measurement was self-reported RTI symptoms in the previous week.

SETTING

Tromsø, Norway, 69 °N.

SUBJECTS

Six thousand three hundred and fifty middle-aged and elderly residents of Tromsø.

RESULTS

Of the 6350 included, 791 (12.5%) reported RTI symptoms in the previous week. We classified serum 25(OH)D concentrations into quartiles and adjusted the data for current smoking habit and month of attendance. The prevalence of RTI symptoms did not increase with decreasing serum 25(OH)D level, was highest in quartile 3 (15.0%) followed by quartile 4 (12.4%), and was lowest in quartiles 1 and 2 (11.1% and 11.4%). There was no trend for increasing duration of illness with decreasing serum 25(OH)D. The prevalence of RTI symptoms was not significantly associated with the intake of fish, n-3 capsules or vitamin and/or mineral supplements, or sun exposure. Only use of cod-liver oil or fish oil capsules daily or sometimes was significantly associated with fewer RTI symptoms during the preceding 7 d (P = 0.04).

CONCLUSIONS

Low serum 25(OH)D was not associated with increased prevalence of recent RTI symptoms. Our findings do not support the idea that vitamin D supplementation can reduce the incidence of RTI in Norway.

Cross-sectional associations between prevalent vertebral fracture and pulmonary function in the sixth Tromsø study

Background

Persons with vertebral fracture may have reduced pulmonary function, but this association has not been much studied. The aim of this cross-sectional study was therefore to examine the relationship between vertebral fracture and pulmonary function in a general, elderly population.

Methods

Vertebral morphometry was used for vertebral fracture assessment in 2132 elderly men (n = 892) and women (n = 1240) aged 55 to 87 years in the population-based Tromsø Study 2007–08. Pulmonary function was examined by spirometry. Pulmonary function was expressed as FVC% predicted, FEV₁% predicted, and FEV₁/FVC% predicted values, adjusted FVC, FEV₁, and FEV₁/FVC, and obstructive and restrictive ventilatory impairment. Vertebral fracture was classified according to appearance, number, severity, and location of fractures. Associations were analyzed using general linear and logistic models.

Results

FVC% predicted and FEV₁% predicted values were not associated with vertebral fracture (P > 0.05), whereas FEV₁/FVC% predicted ratio was associated with both prevalent fracture, number of fractures, severity of fractures, and fracture site in men (P < 0.05), but not in women. When FVC, FEV₁, and FEV₁/FVC values were adjusted for multiple covariates, we found no significant association with vertebral fracture. Obstructive and restrictive ventilatory impairment was not associated with prevalent vertebral fracture.

Conclusions

In conclusion, this study did not confirm any clinically relevant associations between prevalent vertebral fracture and ventilatory impairment in elderly individuals.

Symptoms of respiratory tract infection and associated care-seeking in subjects with and without obstructive lung disease; the Tromsø Study: Tromsø 6

Background

Respiratory tract infections (RTIs) may be more severe in those with asthma or COPD and these patients are more frequently in need of health care. The aim of the study was to describe the frequency of RTI symptoms in a general adult population and how care-seeking is associated with the presence of obstructive lung disease.

Methods

Cross-sectional data including spirometry and self-reported chronic diseases were collected among middle-aged and elderly subjects in the Tromsø population survey (Tromsø 6). Self- reported RTI symptoms, consultations and antibiotic use were the main outcome variables. Possible predictors of RTI symptoms were evaluated by multivariable logistic regression.

Results

Of the 6414 subjects included, 798 (12.4%) reported RTI symptoms in the previous week. RTI symptoms were reported less frequently by subjects aged 75 years or above, than by those younger than 55 years (OR 0.5). Winter season (OR 1.28), current smoking (OR 1.60), low self-rated health (OR 1.26) and moderate to severe bronchial obstruction (OR 1.51), were also statistically significant independent predictors of RTI symptoms, but these variables did not predict RTI symptoms that had started within the previous seven days. Among subjects with RTI symptoms, 5.1% also reported a consultation with a doctor. In those with bronchial obstruction by spirometry, who did not report asthma or COPD, this frequency was 2.4%. Antibiotic treatment was reported by 7.4% of the participants, among whom one third had consulted a doctor. Antibiotics were taken more frequently when asthma or COPD was reported (13.7%), but not in subjects with bronchial obstruction who did not report these diseases (7.2%).

Conclusions

RTI symptoms seldom led to consultation with a doctor and not even in subjects with obstructive lung disease. This was in particular the case in subjects who did not know about their obstructive lung disease. Strategies for early diagnosis of COPD and providing health care to subjects with such disease cannot rely on their doctor visits due to respiratory symptoms.