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Vitamin D deficiency and airflow limitation in the Baltimore Longitudinal Study of Ageing.

ABSTRACT: BACKGROUND:Vitamin D deficiency is common in patients with chronic obstructive pulmonary disease (COPD) and has also been linked to comorbidities often present in COPD. AIM:The aim of this study was to investigate whether vitamin D deficiency was related specifically to airflow limitation or whether vitamin D deficiency was determined by conditions that frequently coexist with COPD: insulin resistance, hypertension, anaemia, obesity and hypercholesterolaemia. METHODS:For this cross-sectional analysis, we included 897 subjects from the Baltimore Longitudinal Study of Aging. Subjects taking vitamin D supplements were excluded. Airflow limitation was defined as FEV1 /FVC < lower limit of normal. Logistic regression was used to assess the association between vitamin D deficiency (25-hydroxy vitamin D < 20 ng/mL) and possible determinants. RESULTS:Vitamin D deficiency was not specific for subjects with airflow limitation. Body mass index (BMI) (OR: 1.05, P < 0.03) and obesity (BMI > 30 kg/m(2)) (OR: 1.9, P < 0.002) were significantly associated with vitamin D deficiency in the adjusted multivariate regression analysis. Physical activity was associated with a decreased risk of vitamin D deficiency. CONCLUSIONS:Airflow limitation was not an independent determinant of vitamin D deficiency. The effect of weight loss and increased physical activity on vitamin D levels should be investigated further in intervention studies.

SUBMITTER: Moberg M

PROVIDER: S-EPMC5189918 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

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Vitamin D deficiency and airflow limitation in the Baltimore Longitudinal Study of Ageing.

Moberg Mia M Elango Palchamy P Ferrucci Luigi L Spruit Martijn A MA Wouters Emiel F EF Rutten Erica P A EP

European journal of clinical investigation 20150807 9

<h4>Background</h4>Vitamin D deficiency is common in patients with chronic obstructive pulmonary disease (COPD) and has also been linked to comorbidities often present in COPD.<h4>Aim</h4>The aim of this study was to investigate whether vitamin D deficiency was related specifically to airflow limitation or whether vitamin D deficiency was determined by conditions that frequently coexist with COPD: insulin resistance, hypertension, anaemia, obesity and hypercholesterolaemia.<h4>Methods</h4>For th ...[more]

PMID: 26173468

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Project description:: Several researchers have assessed the utility of Impulse Oscillometry System (IOS) in diagnosing and evaluating the severity of respiratory diseases in childhood, but none has investigated the impact of the fluctuations of IOS parameters in an individualized manner. In this two-year prospective study, we aimed to longitudinally evaluate changes in airflow limitation and bronchodilator responsiveness in steroid-naïve four- to six-year-old children during a virus-induced wheezing episode, with IOS pulmonary resistance parameters set at 5 (R5) and 20 (R20) Hz. Moreover, feasibility and reproducibility, in addition to the diagnostic properties of these parameters were examined. Lung function was assessed every six weeks (baseline), within the first 48 hours following an acute wheezing episode (Day 0), after 10, and after 30 days. Forty-three out of 93 recruited children (4.5 ± 0.4 years old) experienced a wheezing episode during the study period. All children were able to perform the IOS effort in an acceptable and highly reproducible manner. R5 and R20 fluctuated independently of atopy, age, height, and weight. On Day 0, R5 values were significantly lower than the respective baseline values and returned to individual baseline levels within 10 days. Post-bronchodilation R5 values were similar to the baseline ones, reflecting a reversible airway obstruction on Day 0. Response to bronchodilation (?R5) was significantly more pronounced on Day 0. ?R5 values lower than -20.5% had a sensitivity of 70% and a specificity of 76% and could accurately identify up to 75% of the examined preschoolers. This study provides evidence in favor of the objective utility of IOS as an easy, highly reproducible, and sensitive technique to assess clinically significant fluctuations and bronchodilation responses suggestive of airflow limitation. Reference values although necessary are suboptimal, utilizing the personal best values as personal reference is useful and reliable.

Project description:Study objectivesThe presence of flow limitation during sleep is associated with adverse health consequences independent of obstructive sleep apnea (OSA) severity (apnea-hypopnea index, AHI), but remains extremely challenging to quantify. Here we present a unique library and an accompanying automated method that we apply to investigate flow limitation during sleep.MethodsA library of 117,871 breaths (N = 40 participants) were visually classified (certain flow limitation, possible flow limitation, normal) using airflow shape and physiological signals (ventilatory drive per intra-esophageal diaphragm EMG). An ordinal regression model was developed to quantify flow limitation certainty using flow-shape features (e.g. flattening, scooping); breath-by-breath agreement (Cohen's ƙ); and overnight flow limitation frequency (R2, %breaths in certain or possible categories during sleep) were compared against visual scoring. Subsequent application examined flow limitation frequency during arousals and stable breathing, and associations with ventilatory drive.ResultsThe model (23 features) assessed flow limitation with good agreement (breath-by-breath ƙ = 0.572, p < 0.001) and minimal error (overnight flow limitation frequency R2 = 0.86, error = 7.2%). Flow limitation frequency was largely independent of AHI (R2 = 0.16) and varied widely within individuals with OSA (74[32-95]%breaths, mean[range], AHI > 15/h, N = 22). Flow limitation was unexpectedly frequent but variable during arousals (40[5-85]%breaths) and stable breathing (58[12-91]%breaths), and was associated with elevated ventilatory drive (R2 = 0.26-0.29; R2 < 0.01 AHI v. drive).ConclusionsOur method enables quantification of flow limitation frequency, a key aspect of obstructive sleep-disordered breathing that is independent of the AHI and often unavailable. Flow limitation frequency varies widely between individuals, is prevalent during arousals and stable breathing, and reveals elevated ventilatory drive. Clinical trial registration: The current observational physiology study does not qualify as a clinical trial.

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Dataset Information

Vitamin D deficiency and airflow limitation in the Baltimore Longitudinal Study of Ageing.

Publications

Vitamin D deficiency and airflow limitation in the Baltimore Longitudinal Study of Ageing.

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