The major factors affecting bitcoin are :
Change in government - it's simply means when another government enter there's will be reduction or addition of some policies.
Political instability - when political system in the country is not stable, everything will get down.
What you mean by bitcoin business?
Any business that accepts bitcoin as payment or crypto trading platforms and other sites like casinos, etc?
Only factor that is affecting on the both side is slow transaction processing and high transaction fee.