title: Is low serum 25-hydroxyvitamin D a possible link between pulmonary tuberculosis and type 2 diabetes?
abstract: OBJECTIVE
  Although vitamin D is implicated in the generation of anti-microbial peptide cathelicidin, which plays a key role against pulmonary tuberculosis (PTB), and may have an inverse association with the risk of type 2 diabetes (DM), its role in the co-existence of these two diseases (PTB-DM) is still uncertain. This study explored the association of vitamin D status with prevalent PTB, PTB-DM and DM.
  
  
  METHODS
  We randomly selected 130 PTB patients, 90 PTB-DM, 91 DM and 134 controls. Serum 25(OH)D levels were determined. A structured questionnaire and anthropometric measurements were administered.
  
  
  RESULTS
  Serum 25(OH)D levels in PTB and PTB-DM were 12.2±2.2 ng/mL and 12.9±2.5 ng/mL, respectively, which were lower than those in DM and control groups. Odds ratios of PTB and PTB-DM comparing extreme quartiles of 25(OH)D (lower than 8.6 ng/mL versus >=26.6 ng/mL) were 3.26 and 2.27, respectively. These associations remained after adjustment for possible risk factors [OR (95% CI)=4.73 (2.04-10.9) and 2.50 (1.04- 6.02), respectively]. A synergistic interaction was observed between low 25(OH)D and underweight in respect to prevalent PTB-DM [OR=24.6 vs 2.50 for lowest quartile of 25(OH) D and 4.59 for underweight].
  
  
  CONCLUSIONS
  Odds ratios of low serum 25(OH)D levels for PTB and PTB-DM were greater than 1.0, and were even much greater when combined with underweight. However, since the association of serum 25(OH)D levels with PTB was stronger than with PTB-DM, we could not draw the conclusion that vitamin D is a link between PTB and DM.
authors.affiliation: Institute of Human Nutrition, Medical College of Qingdao University, Qingdao, China.
authors.forename: Qiuzhen
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Institute of Human Nutrition, Medical College of Qingdao University, Qingdao, China. Email: ma91503@126.com.
authors.forename: Aiguo
authors.initials: A
authors.lastname: Ma
authors.affiliation: Institute of Human Nutrition, Medical College of Qingdao University, Qingdao, China.
authors.forename: Xiuxia
authors.initials: X
authors.lastname: Han
authors.affiliation: Qingdao Institute For Food and Drug Control, Qingdao, China.
authors.forename: Huizhen
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Linyi Chest Hospital, East Fenghuang Avenue, Linyi, China.
authors.forename: Shanliang
authors.initials: S
authors.lastname: Zhao
authors.affiliation: Institute of Human Nutrition, Medical College of Qingdao University, Qingdao, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Liang
authors.affiliation: Institute of Human Nutrition, Medical College of Qingdao University, Qingdao, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Cai
authors.affiliation: Division of Human Nutrition, Wageningen University, Wageningen, The Netherlands.
authors.forename: Frans J
authors.initials: FJ
authors.lastname: Kok
authors.affiliation: Division of Human Nutrition, Wageningen University, Wageningen, The Netherlands.
authors.forename: Evert G
authors.initials: EG
authors.lastname: Schouten
mesh_terms: D000328:Adult; D000368:Aged; D015992:Body Mass Index; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009752:Nutritional Status; D016017:Odds Ratio; D012307:Risk Factors; D013851:Thinness / Q000150:complications; D014397:Tuberculosis, Pulmonary / Q000097:blood* / Q000453:epidemiology; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000150:complications*
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D