I would discuss your question with your primary doctor
. Both conditions can be fairly troublesome and occasionally have serious complications and therefore warrant close follow up.
In general, GERD doesn't cause high blood pressure
. GERD, or gastroesophageal reflux disease is when the acidic juices of the stomach "reflux" up into the esophagus, or the food pipe. These juices causes the sensation of heartburn, give an acidic or bitter taste in the mouth, or sometime chronic cough. Occasionally, the longstanding reflux can cause the esophagus to change and rarely cause cancer.
High blood pressure is a separate diagnosis that is often genetic. Factors, like weight, salt, family history, ethnicity and even stress are involved. 95% of all hypertension is primary--which means we are not completely sure why it occurs.
While it is unlikely that one causes the other, there is a relationship between the two. Both conditions are common in individuals who are overweight or obese. Therefore, it is common for many people to have both. Being overweight causes elevation in blood pressure, and also separately increases pressure in the stomach which results in the reflux. Therefore losing weight can help both diseases. Stress is related to both as well, however probably a smaller factor. There are rare pancreatic or small bowel cancers that could theoretically cause both--however this would be a one in a million diagnosis.
Talk to your doctor. In general, maintaining an ideal body weight can help both diseases. If you are overweight, this is likely the root cause of both.