title: Undiagnosed severe sleep apnoea and diabetic foot ulceration - a case series based hypothesis: a hitherto under emphasized factor in failure to heal.
abstract: BACKGROUND
  Although great progress has been made in managing diabetic foot disease, it continues to carry significant morbidity and mortality. Obstructive sleep apnoea (OSA) and diabetes frequently coexist and recent studies suggest significant under-recognition of OSA in those with diabetes. There are no current reports on the direct clinical impact of OSA on acute or chronic diabetic foot ulcer healing.
  
  
  METHODS
  We describe three cases with Type 2 diabetes and a mean BMI of 50 kg/m(2) in whom we believe undiagnosed severe OSA may have impeded the rate of recovery of acutely infected foot ulcers. Despite standard care whilst in hospital with optimization of glycaemia, daily wound care, ulcer offloading techniques including casting, it was difficult to achieve satisfactory granulation in the first two cases with previously unrecognized and hence untreated severe OSA (Apnoea-Hypopnea Index > 30) until correction had been achieved through continuous positive airway pressure therapy (CPAP). In the third case, despite all optimization techniques, healing has not been achieved and individuals' reluctance to consider CPAP may be one possible factor.
  
  
  CONCLUSIONS
  We observe in three severely obese individuals with diabetes that untreated severe OSA may have contributed to delayed wound healing. We also observed an improvement in two individuals after institution of CPAP therapy. Clinicians managing the diabetic foot should consider investigating the presence of OSA in non-healing or slowly progressive foot ulcers when all other factors have been fully optimized.
authors.affiliation: Kings Diabetes Foot Clinic, London, UK.
authors.forename: P R J
authors.initials: PR
authors.lastname: Vas
authors.affiliation: Department of Orthopaedics, Kings College Hospital, London, UK.
authors.forename: R
authors.initials: R
authors.lastname: Ahluwalia
authors.affiliation: Kings Diabetes Foot Clinic, London, UK.
authors.forename: A B
authors.initials: AB
authors.lastname: Manas
authors.affiliation: Kings Diabetes Foot Clinic, London, UK.
authors.forename: C A
authors.initials: CA
authors.lastname: Manu
authors.affiliation: Department of Orthopaedics, Kings College Hospital, London, UK.
authors.forename: V
authors.initials: V
authors.lastname: Kavarthapu
authors.affiliation: Kings Diabetes Foot Clinic, London, UK.
authors.forename: M E
authors.initials: ME
authors.lastname: Edmonds
mesh_terms: D003131:Combined Modality Therapy; D045422:Continuous Positive Airway Pressure; D057210:Delayed Diagnosis; D003924:Diabetes Mellitus, Type 2 / Q000150:complications*; D017719:Diabetic Foot / Q000150:complications* / Q000382:microbiology / Q000534:rehabilitation / Q000628:therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications*; D009767:Obesity, Morbid / Q000150:complications*; D010349:Patient Compliance; D012720:Severity of Illness Index; D020181:Sleep Apnea, Obstructive / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology / Q000628:therapy; D018461:Soft Tissue Infections / Q000150:complications / Q000382:microbiology; D016896:Treatment Outcome; D014945:Wound Healing