Well, there is something in the insurance industry called coordination of benefits or COB. If for example an employee or plan member has access to a spousal plan for drugs, often there is a sharing of the costs. Each plan will cover a portion of the cost of prescription drugs , or dental services etc. It is a way in which a plan actually can save money while providing employees and plan members a higher level of service.
So in the case of a business closing and perhaps hundreds or even thousands of employees effected by this, the net result will be to increase costs on a spousal plan. Even though the two industries may not be related , the job loss is felt by the other industry. If two plans were each covering $50 of a monthly drug spend , one will now have to cover the full $100 thus premiums will rise faster than anticipated.
Another area impacted by this is at the physician level. Some of these folks are not going to have a drug plan and they may end up at the physicians office looking to change medications or help with samples (Only the new products are found there and usually at a higher price) . Some, patients may stop taking their medications all together thereby increasing their risk of more serious events. Both of these add to the cost of our public plans.