I don’t “do” social media much any more but I have recently joined what looks like a relevant online community for those with an interest in health information management: Digital Health Networks. As a “community of NHS IT leaders” it is understandably focused on applications of (mostly commercial) IT in the NHS context, rather than my area of doing things for free in low and middle-income countries. But other than the DHIS2 Community that I have occasionally contributed to this is the closest matching interdisciplinary linkup I have found. I did an intro here. There are various private forums you can apply to join (I have joined the cybersecurity one as this is the part of the work that keeps me awake at night) and I might apply to join the Faculty of Clinical Informatics at some point.