Meta-analysis of vitamin D and lung function in patients with asthma

Abstract

Background There is growing literature suggesting a link between vitamin D and asthma lung function, but the results from systematic reviews are conflicting. We conducted this meta-analysis to investigate the relation between serum vitamin D and lung function in asthma patients. Methods Major databases, including OVID, MEDLINE, Web of Science and PUBMED, were searched until 10th October 2018. All published observational studies related to vitamin D and asthma were extracted. All meta-analyses were performed using Review Manager 5.3.5. Results This quantitative synthesis found that asthma patients with low vitamin D levels had lower forced expiratory volume In 1 s (FEV1) (mean difference (MD) = − 0.1, 95% CI = − 0.11 to − 0.08,p < 0.01;I2 = 49%, p = 0.12) and FEV1% (MD = − 10.02, 95% CI = − 11 to − 9.04, p < 0.01; I2 = 0%, p = 0.82) than those with sufficient vitamin D levels. A positive relation was found between vitamin D and FEV1 (r = 0.12, 95% CI = 0.04 to 0.2, p = 0.003; I2 = 59%,p = 0.01), FEV1% (r = 0.19, 95% CI = 0.13 to 0.26, p < 0.001; I2 = 42%, p = 0.11), forced vital capacity (FVC) (r = 0.17, 95% CI = 0.00 to 0.34, p = 0.05; I2 = 60%, p = 0.04), FEV1/FVC (r = 0.4, 95% CI = 0.3 to 0.51, p < 0.001; I2 = 48%, p = 0.07), and the asthma control test (ACT) (r = 0.33, 95% CI = 0.2 to 0.47, p < 0.001; I2 = 0%, p = 0.7). Subgroup analysis indicated that the positive correlation between vitamin D and lung function remained significant in both children and adults. Conclusions Our meta-analysis suggested that serum vitamin D levels may be positively correlated with lung function in asthma patients. Future comprehensive studies are required to confirm these relations and to elucidate potential mechanisms.

Serum vitamin D is associated with improved lung function markers but not with prevalence of asthma, emphysema, and chronic bronchitis

“…Also in smokers, we observed a similar relationship with lung function markers. Similar to our findings, a meta-analysis on 27 studies suggested that serum 25(OH)D concentration was directly associated with lung function in asthma patients 31,32 . Another study conducted on 2,607 adolescents aged 15 years found that serum 25(OH)D concentrations were directly associated with FVC and FEV 1 .…”

Controversies in Vitamin D: A Statement From the Third International Conference

“…Pulmonary, blood pressure, and other effects Additionally, from the VIDA trial, central blood pressure was significantly reduced in patients taking vitamin D supplementation (−7.5 mmHg, p = 0.03), (157) and the number of patients taking NSAIDs was significantly reduced (RR, 0.87, p = 0.01). (158) Furthermore, giving vitamin D to the normal population and to the vitamin D-deficient population improves lung function, (159) in line with a meta-analysis, (160) as well as reducing age-related bone loss. (161,162) In an individual participant data meta-analysis of 15 RCTs, daily or weekly supplementation in individuals with vitamin D deficiency, defined as a serum 25OHD level <10 ng/ mL, reduced risk of acute respiratory infection by 30% (odds ratio, 0.30; 95% CI, 0.17-0.53).…”

Vitamin‐D supplementation as an adjunct to standard treatment of asthma in children: A randomized controlled trial (ViDASTA Trial)

“…Median (first-third quartile), n (%) Although observational studies showed a low level of vitamin D level in children with asthma, however, experimental studies on vitamin D supplementation in asthma in children showed conflicting evidence. [13][14][15][16] Therefore, the conventional concept of vitamin D therapy in asthma may work by its immunogenic effect is still controversial.…”