Asymmetries in reciprocal baroreflex mechanisms and chronic pain severity: Focusing on irritable bowel syndrome

Abstract

We anticipate the findings to be a starting point for validating these autonomic metrics of pain suffering and pain coping mechanisms in other chronic pain syndromes to suggest them as biomarkers of its severity and duration for profiling and correct management of chronic pain patients.

Cardiovascular phenotyping for personalized lifestyle treatments of chronic abdominal pain in Irritable Bowel Syndrome: A randomized pilot study

“…However, the findings also predict that incorrect predominant management of somatic or affective complaints in patients with mainly an affective or somatic mechanism of chronic pain, respectively, will not improve effectiveness of the intervention. Thus, these results are in accord with previous considerations that impacts of affective and somatic components of chronic pain on the patient's condition should be correctly distinguished for their effective management …”

“…Baroreceptor sensitivity and other baroreflex indexes were measured by the sequence method . SBP and RR‐interval (RRI) time series were scanned by custom software (see below) to identify sequences during which SBP and associated RRI both increased (“up” [+] sequences) or both decreased (“down” [–] sequences) successively in parallel over three or more beats (SBP and RRI ramps).…”

“…We required a minimum change of 1 mm Hg for SBP and 3 ms for RRI per beat and a minimum correlation of 80 between the parallel values to accept the pairs for calculating BRS (gain of baroreceptor sensitivity, ms/mm Hg), and separately BPS (mm Hg/beat, gain of SBP ramps, short‐term SBP falls and rises triggering RRI baro‐responses, −BPS, and +BPS, respectively) and RRIS (ms/beat, gain of RRI ramps, short‐term tachycardiac and bradycardiac baro‐responses, −RRIS and +RRIS, respectively) as means of least squares linear regression slopes with lag 0, 1, and 2 . Means of SBP start point or the first SBP reading of SBP ramp in the baroreflex sequences for initiation of down (−SPBP) and up (+SPBP) baroreflex reactions (the highest set point for down sequences and the lowest set point for up sequences or baroreflex down and up operational points) were also indicated to evaluate the effects of the baroreceptor resetting . A range between +SPBP and −SPBP values was also assessed as an indicator of the effectiveness of baroreflex regulation of the amplitude of spontaneous BP fluctuations.…”

“…Baroreceptor sensitivity and other baroreflex indexes were measured by the sequence method. 23,38,42 SBP and RR-interval (RRI) time series were scanned by custom software (see below)…”

“…[15][16][17][18][19] In the first case, individual genotypes or endophenotypes associated with these cardiovascular (CV) variables have been proposed as moderators of health resiliency, both in general, and against pain, in particular. [20][21][22][23][24][25] For example, prior studies have shown that a family history of hypertension in normotensive humans and presence of hypertension predicted lower pain intensity or higher pain thresholds. 26,27 This corresponds with findings that a genetic predisposition to higher sympathetic activation in response to painful stimuli in people with the LL genotype of the serotonin transporter-linked polymorphic region (5-HTTLPR) was reliably associated with higher pain thresholds and more habituation to acute visceral and somatic pain compared with people with the s allele of the 5-HTTLPR, and the association was stable at a period of 1 year.…”