Background: We examined whether a series of variables were related to the number of psychiatric inpatients using publicly available data about English psychiatric bed utilisation and NHS workforce. Method: Using linear regression, with auto-regressive errors, we examined relationships between variables over time using data from December 2013 to March 2021. Results: Over time, the number of inpatients reduced by either 6.58 or 8.07 per month depending upon the dataset utilised, and the number of community nurses and community nursing support staff reduced by 7.43 and 2.14 nurses per month, respectively. Increasing numbers of consultant psychiatrists were associated with fewer inpatients over time. More care and treatment reviews (CTRs) were associated with more admissions over time, while more post-admission CTRs were associated with increased discharges over time. Conclusions: Future studies should examine whether psychiatric bed utilisation elsewhere within the NHS by people with intellectual disabilities has increased.