If have connected your Apple Health App to Pattern and you wish to change which data is being synced, you can do this from the Apple Health App.
Open the Apple Health App, navigate to the Sources screen and select the Pattern app.
Then, select the option you wish to change Health Records or Health Data.
From there you will be able to turn the data sync for each type on or off.
You can also choose to unlink the Apple Health App in the Pattern app.
Go to the More menu, select Connected Devices then tap on Apple Health App.
You can then select Unlink, to remove the Apple Health App as a connected device.
This will then stop all future health data and medications from syncing to the Pattern app.