Gut prob­lems may be early sign of Parkin­son’s dis­ease

Con­sti­pa­tion, dif­fi­culty swal­low­ing and ir­ri­ta­ble bowel symp­toms are pos­si­ble mark­ers, say re­searchers.

Gut prob­lems in­clud­ing con­sti­pa­tion, dif­fi­culty swal­low­ing and an ir­ri­ta­ble bowel may be an early warn­ing sign of Parkin­son’s dis­ease in some peo­ple, a new study sug­gests. 

The find­ings in the jour­nal Gut add more ev­i­dence to the idea that brain and bowel health are in­ti­mately linked. 

Un­der­stand­ing why gut is­sues hap­pen might al­low ear­lier treat­ment of Parkin­son’s, say the re­searchers. 

Parkin­son’s is pro­gres­sive, mean­ing the brain dis­or­der gets worse over time. 

Peo­ple with Parkin­son’s do not have enough of the chem­i­cal dopamine in their brain be­cause some of the nerve cells that make it are dam­aged.

This causes symp­toms in­clud­ing in­vol­un­tary tremor or shak­ing, slow, shuf­fling move­ments and stiff mus­cles. 

Al­though there is cur­rently no cure, treat­ments are avail­able to help re­duce the main symp­toms and main­tain qual­ity of life for as long as pos­si­ble. 

Spot­ting the dis­ease even sooner – be­fore neu­ro­log­i­cal symp­toms ap­pear and there is sub­stan­tial brain cell dam­age – might make a big dif­fer­ence.

For the study, re­searchers analysed US med­ical records of 24,624 peo­ple with Parkin­son’s, com­par­ing them with:

What they wanted to find out was:

The an­swer that came back for both ques­tions was “yes”, based on five years of data. 

Specif­i­cally, four gut con­di­tions – con­sti­pa­tion, dif­fi­culty swal­low­ing, gas­tro­pare­sis (a con­di­tion that slows the move­ment of food to the small in­tes­tine) and ir­ri­ta­ble bowel – were as­so­ci­ated with a higher risk of Parkin­son’s. 

Ap­pen­dix re­moval, how­ever, seemed to be pro­tec­tive, which is some­thing that other sci­en­tists have recog­nised be­fore.

Not every­one with gas­troin­testi­nal prob­lems will go on to get Parkin­son’s, the re­searchers stress, but there ap­pears to be some kind of link be­tween gut and brain health. 

The gas­troin­testi­nal tract has mil­lions of nerve cells that com­mu­ni­cate with the brain. Ex­perts say it is pos­si­ble that ther­a­pies that help one sys­tem might also help the other, or that an ill­ness in one re­gion will af­fect the other.   

Clare Bale, from Parkin­son’s UK, said the re­sults “add fur­ther weight” to the hy­poth­e­sis that gut prob­lems could be an early sign of the dis­ease.

Prof Kim Bar­rett, from Uni­ver­sity of Cal­i­for­nia, Davis, said more stud­ies were needed to un­der­stand whether the link was some­thing that could be used by doc­tors to help pa­tients. 

“It re­mains pos­si­ble that both gas­troin­testi­nal con­di­tions and Parkin­son’s dis­ease are in­de­pen­dently linked to an as yet un­known third risk fac­tor – the work re­ported can­not as­cribe causal­ity.  

“Nev­er­the­less, the con­clu­sions may have clin­i­cal rel­e­vance, and cer­tainly should prompt ad­di­tional stud­ies.”

Dr Tim Bar­tels, from the UK De­men­tia Re­search In­sti­tute at Uni­ver­sity Col­lege Lon­don, said the work firmly es­tab­lishes that the gut might be a “prime tar­get” to search for bio­mark­ers of Parkin­son’s – mea­sur­able phys­i­cal changes that can act as an early warn­ing sign. 

He said be­ing able to pre­dict Parkin­son’s ear­lier would be “highly valu­able for ear­lier, and there­fore more ef­fec­tive, treat­ment and drug tar­get­ing”. 

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