Caffeine Articles

Researchers looking at coffee oils for a cause of gallstones found to be from eating tamarind fruit.
Cafestol Coffee oils raise cholesterol especially triglycerides LDL HDL. This is reproducible in healthy individuals. 2005
Coffee bean extracts kahweol elevate liver enzymes in healthy individuals. 2004
Coffee - Association Parkinson's and coffee
Caffeine - Abstract - Chronic consumption exacerbates hypertension in PKD rats
Caffeine - Full article - Chronic consumption exacerbates hypertension in PKD rats
Coffee - Caffeine increases kidney stones formation. (Massey 2004)
Caffeine's effect on PKD stimulates cyst growth by stimulating C-amp. Rapidly can lead to decline in kidney functioning.
Coffee PKD stimulates cyst growth in PKD kidneys by stimulating C-amp.
Coffee stimulates bad cholesterol NY times article
BP Caffeine- Habitual caffeine intake and risk of hypertension in women
Coffee caffeine alters signaling LVH to the heart ADPKD cardiomyocytes altered signaling.
Coffee caffeine alters smooth muscle calcium stores vascular phenotype in PKD Torres Somlo 2007.
Caffeine increases excretion of minerals for 3 hours contributes to lessening bone density.
Decaffeinated' Coffee May Be Anything But

Many of us with PKD and PLD have observed that by eliminating caffeine we have a lessening of pain surrounding our cystic kidneys and cystic liver. Caffeine stimulates cyclic AMP. Cyclic AMP increases cyst growth and expansion. Tolvaptan an experimental drug to reduce kidney cyst growth. One mechanism of tolvaptan is that it blocks the binding at receptor sites of cyclic AMP. Even small amounts of caffeine contained in de-caf chocolate or de-caf organic green tea have increased pain within our cystic kidneys, as well as increased abdominal girth from cyst expansion and growth.

Caffeine contributes to increased mineral excretion in the urine, increased kidney stone formation; increased PKD cysts formation; and it raises PKD blood pressure. Blood pressure elevation contributes to the many vascular and cardiac manifestations of PKD - such as LVH or left ventricular hypertrophy. Many PKD'rs are maintaining blood pressure near 100/70 - 110/70 - 120/80. This low blood pressure is thought to be key in delaying dialysis by 15 years or more. Whereas uncontrolled blood pressure is thought to cause a much more rapid decline in kidney functioning. The number one cause of death from Polycystic Kidneys is left ventricular hypertrophy— LVH heart disease. It is not kidney disease. Cystic kidneys do fail but generally this is not what causes death, it is the heart and the blood vessels. This is why there is such an interest in cardiomyocytes, caffeine and polycystin 2. There is an ongoing 5 year HALT PKD blood pressure trial underway. Check out the HALT website or send an email if you are willing to volunteer. More on research and other clinical trials is available here. Caffeinated beverages should be discouraged because caffeine inhibits phosphodiesterase; enhances cAMP accumulation; and potentiates the effects of vasopressin on chloride secretion, cell proliferation, and cyst growth, at least in vitro (27).
27. Belibi FA, Wallace DP, Yamaguchi T, Christensen M, Reif
G, Grantham JJ: The effect of caffeine on renal epithelial
cells from patients with autosomal dominant polycystic
kidney disease. J Am Soc Nephrol 13: 2723–2729, 2002