Level of Evidence: 3 Objective(s) To identify the risk factors for Cholesteatoma in a large UK cohort. Although some risk factors are well established (male sex, history of chronic otitis media), others require further evidence (deprivation, smoking). Design and Setting 1,140 cholesteatoma cases from UK BioBank were compared to 4,551 non-cholesteatoma middle ear disease and 493,832 ear disease-free controls. Adjusted odds ratios were calculated for demographic factors including age, sex, ethnicity, deprivation and smoking status with logistic regressions. Odds ratios for overlapping ICD-10 codes are also calculated. Results Cholesteatoma was significantly associated with sex (Adjusted odds ratio (AOR) for males=1.33), age (AOR=1.02) and deprivation (AOR=1.08) compared to ear disease-free controls ( p<0.001). Age and deprivation distributions for cholesteatoma and non-cholesteatoma ear disease were similar. Although there was no significant association with smoking status, cholesteatoma was significantly associated with the ICD-10 code mental and behavioural disorders due to tobacco use (OR=2.34, p<0.001). Cholesteatoma was also strongly associated with a wide range of inflammatory middle ear conditions and chronic sinus inflammation, suggesting an increased susceptibility to inflammation of the upper airways. Conclusion This study shows a large overlap between cholesteatoma and non-cholesteatoma ear disease in terms of numbers and demographics, with sex being a key factor distinguishing between the two, suggesting that there are both common and distinct risk factors exist.

Objectives Admission of patients with necrotising otitis externa (NOE) has been rising steadily over the last five years and mortality and morbidity associated with the disease is high. Our objective is to assess the value of adjuvant hyperbaric oxygen therapy in patients with necrotising otitis externa. Design and setting A retrospective, observational, case-control study was conducted by examining patients’ records over a four-and-a-half-year period at two secondary care sites in the UK. The (Non-HBO) control group treated conventionally and the (HBO) group treated with additional adjuvant HBO in a multiple occupancy therapy chamber at the James Paget University Hospital. The primary outcome measure was death. Secondary outcomes measures were resolution of pain and recovery from otalgia, facial nerve palsy and other cranial nerve palsies. Results There were 10 patients in the HBO group and 20 in the non-HBO group; mean age was 82.3 years and 88.3 years respectively. The mortality rate was 30% in the HBO group compared to 55% in the non-HBO group. Patients tolerated HBO well, had greater resolution of pain (90% vs 64%) and resolution of facial nerve palsy (67% vs 31%) than the non-HBO group. Resolution of other cranial neuropathies was similar. Conclusion Our case series suggests that HBO is potentially a life-saving intervention. It also suggests that patients treated with HBO therapy for NOE appear to improve both in terms of pain and facial nerve palsies compared with conventional treatment and sets the precedent for a trial to formally compare the adjunctive intervention of HBO.