Abnormal ventilatory responses to hypoxia in Type 2 diabetes

Diabet Med. 2005 May;22(5):563-8. doi: 10.1111/j.1464-5491.2005.01458.x.


Aims: The incidence of Type 2 diabetes is increasing, along with its associated micro- and macrovascular disease manifestations. Previous studies indicate that patients with Type 2 diabetes exhibit abnormal cardiopulmonary reflex responses to various stimuli, although the impact of hypoxia, a common physiological stimulus, on ventilatory responses has not previously been studied in humans with Type 2 diabetes.

Methods: Minute ventilation (V(E)) breathing pattern responses (total breath time, T(TOT); expiratory time, T(E); inspiratory time, T(I); inspiratory duty cycle, T(I)/T(TOT)) were measured during 5 min each of normoxia and isocapnic hypoxia (arterial O2 saturation approximately 85%) in eight subjects with Type 2 diabetes and seven age- and body mass index-matched healthy subjects.

Results: During normoxia, V(E) was similar in control and diabetic subjects (6.4+/-1.2, 6.4+/-1.1 l/min, respectively). In response to hypoxia, V(E) significantly increased in both groups (to 17.0+/-5.0 and 9.5+/-2.0 l/min, respectively, P<0.05), but the magnitude of increase in V(E) was significantly less in diabetic than in control subjects (P<0.05). In addition, the breathing pattern response to hypoxia differed between groups in terms of T(I)/T(TOT) and T(TOT) (P<0.05), with control subjects significantly decreasing T(TOT) and T(E) (P<0.05) while diabetic subjects tended to increase both.

Conclusions: Relative to matched control subjects, Type 2 diabetic subjects exhibit blunted V(E) responses to acute isocapnic hypoxia, suggesting that this group of diabetic subjects possesses a chemoreflex ill-equipped to respond homeostatically to hypoxic challenge.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Diabetes Mellitus, Type 2 / complications
  • Diabetes Mellitus, Type 2 / physiopathology*
  • Female
  • Forced Expiratory Volume / physiology
  • Humans
  • Hypoxia / etiology
  • Hypoxia / physiopathology*
  • Lung Volume Measurements
  • Male
  • Middle Aged
  • Respiration Disorders / etiology
  • Respiration Disorders / physiopathology*