Relationship Between Diabetes Control and Pulmonary Function in Insulin-Dependent Diabetes Mellitus LUISC. RAMIREZ, M.D., ANTHONY DAL NOGARE, M.D., CONNIEHSIA, M.D., CARLOS ARAUZ,M.D., IRFAN BUTT, M.s., SUZANNEM. STROWIG, M.s.N., LAURA~CHNURR-BREEN, B.s.N., PHILIPRASKIN,M.D., Da//as, Texas PURPOSE: To evakate the effect of different levels of glycemic control on the pulmonary function of subjects with type I insulin-depen- dent diabetes mellitus. PATIRNTS AND MEI’IIODB: Eighteen subjects with type I insulin-dependent diabetes mellitus with no history or physical fmdings of respira- tory disease. Patients were given iusulin therapy with a standard twice-daily insulin injection regimen (standard treatment group) or a subcu- taneous insulin infusion device (insulin pump) (intensive treatment group). Glycosylated hemo- globin (HbAl,) levels were determined at quar- terly intervals in both groups of patients (&an- dard treatment group, n = 10; intensive treatment group, n = 8). Puhnonary function and diffusing capacity for carbon monoxide (DLco) were measured after 6 years of continu- ous follow-up. RRSUL!IEk The average HbA1, in the standard treatment group was significantly higher than that of the intensive treatment group through- out the 6 years of follow-up (p <O.OOl). The forced vital capacity of the standard treatment group was 66 f 3% of predicted as compared with 106 f 4% of predicted in the intensive treatment group (p <O.OOl). The DI..co was also significantly dimininhed in the standard treat- ment group as compared with that in the inten- sive treatment group (66 f 2% versus 87 f 4% of predicted) (p <O.OOl). CONCLUSION: TherJe data confirm previous re- ports of abnormal respiratory function in subjects with insulindependent diabetes mellitus and sug- gest that long-term near-normoglycemia may be beneficial in preventing the deterioration of pul- monary function associated with diabetes mellitua From the University of Texas Southwestern Medical Center, Dallas, Texas. This work was supported in part by Grant MOl-RR00633 from the National Institutes of Health. This study was presented in part at the 50th Annual Meeting and Scien- tific Sessions of the American Diabetes Association, Atlanta, Georgia, June 16-19, 1990, and published in abstract form (Diabetes 1990; 39 Suppl 1: 94A). Requests for reprints should be addressed to Philip Raskin, M.D., Uni- versity of Texas Southwestern Medical Center, 5323 Harry Hines Boule- vard, G5.222, Dallas, Texas 75235-6856. Manuscript submitted February 4, 1991, and accepted in revised form May 29,1991. D iabetes mellitus is a systemic diseasewith complications that affect the eye,the kidney, andthe nervous system [l]. The heart [2] and hand [3] may also be intrinsically affected by diabetes, but the abnormalities in these organs have an un- certain clinical relevance. In addition, many other organ abnormalities have been described in dia- betic patients. There have been reports of abnor- malities in skin [4], liver function [5], collagen me- tabolism [6], and taste [7]. Thus, diabetes is a multisystem disease that affects many organs of the body. There is a growing body of evidenceto suggest that the respiratory system is also affectedby dia- betes. In 1976, Schuyler et al [8] reporteddecreased total lung capacity (TLC) in a groupof nonsmoking patients with type I diabetes who had no history of previous lung disease. This finding was confirmed by additional reports that described a wider range of abnormalitiesin the pulmonary function of sub- jects with type I diabetes, including reduced pulmo- nary diffusing capacityand decreased alveolarcap- illary blood volume [9,10]. The etiology of diabetic complications is still a matter of debate [11,12]. The advent of blood glu- coseself-monitoring has made it possible for pa- tients to employ intensive insulin regimens to achieve nearnormal glycemiclevels [13,141. Results from prospective studiescomparinggroupsof sub- jects using intensive insulin therapy as compared with standard insulin regimens have provided rea- sonable evidence to suggest that chronic hypergly- cemiais related to the development and progression of diabetic complications [15,161. This study wasdesigned to investigatethe effect of glycemic control on the pulmonary function of subjects with type I insulin-dependent diabetes mellitus. PATIENTSAND METHODS Subjects The study population wasmadeup of 18 patients with insulin-dependent diabetes mellitus who have been followed continuously since at least 1984 at the University of Texas Southwestern Medical Center at Dallas, Texas. At the beginning of the trial, the patients were giventhe option of selecting their insulin treatment program. They wereoffered October 1991 The American Journal of Medicine Volume 91 371