The Characteristics And Risk Factors For The Development Of Active Pulmonary Tuberculosis In Patients With Type 2 Diabetes Mellitus

Objective:Type 2 diabetes mellitus(DM)is a moderate strong risk factor for active pulmonary tuberculosis(PTB).Several studies have shown that DM is associated with an increased risk of tuberculosis.In recent years,diabetes prevalence has increased worldwide as a result of population ageing,urbanisation,and lifestyle changes,especially in low-and middle-income countries.Meanwhile,the burden of tuberculosis is heavy in these countries.Accompanied with DM can bring adverse effects on the clinical treatment and prognosis of tuberculosis,such as prolonging PTB sputum smear negative time,and increasing the risk of treatment failure,death,and relapse among patients with tuberculosis.Therefore,to identify the characteristics of type 2 diabetes mellitus complicated with active pulmonary tuberculosis(DM-PTB)and the risk factors of PTB in DM patients can provide an important scientific basis for TB prevention and control.We used multivariate conditional logistic regression analysis to explore the characteristics and risk factors for the development of active pulmonary tuberculosis among type 2 diabetes mellitus.Methods:A hospital-based 1:2 matched case-control study was conducted in Shandong province in North China from 2016 to 2017.Study subjects were divided into case group(DM-PTB)and control group(DM).The case group included newly detected PTB who had already diagnosed DM in a chest hospital of a certain city,and type 2 diabetes mellitus alone(DM)who were admitted to a general hospital of a certain city as the control group.we randomly chose up to two population control subjects for each case subject,individually matched on age(±3 years),sex,DM course(±5 years).All patients were subjected to questionnaire survey,physical radiological examination and laboratory investigations.Univariate and multivariable conditional logistic regression analysis was run to examine the risk factors for PTB in DM.Crude and adjusted odds ratios(OR)and 95 % confidence intervals(CIs)are presented.Results:315 participants(105 DM-PTB and 210 DM)were recruited in the study.Body mass index,systolic blood pressure,diastolic blood pressure and lymphocyte count in case group were significantly lower than those in control group,while fasting blood glucose and high density lipoprotein cholesterol levels were significantly higher in case group than in control group.Univariate logistic regression model showed that poor glycemic control,hypoproteinemia,lymphocytopenia,tuberculosis exposure history,room unventilated,high infection,smoking,drinking,difficulty falling asleep and habitual snoring were associated with increased risk of PTB.However,married,high education level,hypertension,oral hypoglycemic drugs with insulin treatment,overweight,obesity,better kitchen ventilation and regular exercise were associated with lower risk of PTB.Five risk factors and two protective factor were ascertained by multivariate regression analysis.Lymphocytopenia(OR=17.75,95% CI: 3.40-92.74),poor glycemic control(OR=3.37,95% CI: 1.11-10.25),smoking(OR=12.25,95% CI: 2.53-59.37),tuberculosis exposure history(OR=6.56,95% CI: 1.23-35.03)and habitual snoring(OR=8.86,95%CI: 1.99-39.45)were independent risk factors for DM-PTB,while the overweight(OR=0.23,95%CI: 0.08-0.72),the obese(OR=0.11,95%CI: 0.02-0.72)and better kitchen ventilation(OR=0.16,95%CI: 0.04-0.59)were protective factors.Conclusion:DM-PTB patients tend to be low education,poor glycemic control,and higher infection.The proportion of smoking,drinking,irregular exercise,and poor sleep quality in patients with DM-PTB were significantly higher than those in DM patients.Lymphopenia,smoking,habitual snoring,tuberculosis exposure history,and poor glycemic control are independent risk factors for PTB.Overweight and obesity are associated with reduced risk of PTB in DM patients.Keeping the kitchen well ventilated may reduce the risk of PTB in diabetics.