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- Stjernbrandt, Albin, 1985-
(author)
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Cold exposure and health : A study on neurological and vascular hand symptoms in northern Sweden
- 2021
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Doctoral thesis (other academic/artistic)abstract
- Background: Living in a cold climate is associated with several adverse health effects. The main purpose of this thesis was to describe cold exposure characteristics in northern Sweden, and investigate the associations between such exposure and the reporting of neurological and vascular hand symptoms. One common cold-related hand symptom is Raynaud’s phenomenon, defined as episodic attacks of acral pallor or cyanosis. There is evidence to suggest that cold exposure can act both as a causal factor and a trigger for such vasospastic symptoms. Other important associated factors include exposure to hand-arm vibration and the presence of rheumatic disease. A somewhat similar clinical entity, cold sensitivity, is defined as a collection of acquired symptoms, resulting in an abnormal aversion to cold, with pain, sensory alterations, stiffness, or color changes, which may occur after a traumatic injury. The condition is hypothesized to mainly originate from nerve injury. The effects of cold exposure on hand function, the occurrence of cold sensitivity in the general population, the link between cold exposure and cold sensitivity, as well as the interface between cold sensitivity and Raynaud’s phenomenon are not fully understood. Therefore, this thesis was also intended to expand the knowledge on Raynaud’s phenomenon and cold sensitivity.Methods: Postal surveys were sent to a sample of men and women between 18 and 70 years of age, living in Norrbotten, Västerbotten, Västernorrland, and Jämtland, drawn from the national Swedish population register. The first survey collected data on 12,627 subjects, and the results were used to describe cold exposure characteristics, and broadly investigate the statistical associations with different neurological and vascular hand symptoms (Paper I). A follow-up survey was sent to a subset of responders, to form nested case–control studies on cold sensitivity (N=1,230; Paper II) and Raynaud’s phenomenon (N=1,400; Paper III). Subjects with cold sensitivity (N=12) from Paper II were subsequently recruited to a laboratory study, to investigate the vascular and neurosensory function of the hands, by means of physical examination, laser speckle contrast analysis before and after cold stress testing, and thermal quantitative sensory testing (Paper IV). Finally, healthy controls (N=1,239) from the case–control studies were used as a reference population for the Cold intolerance symptom severity questionnaire, to establish a cut-off for abnormal cold sensitivity (Paper V).Results: In Paper I, cold exposure was commonly reported, both during work and leisure time. Exposure was most pronounced in alpine regions, generally higher among men than women, and decreased with age. Highly cold-exposed occupational groups were militaries; agricultural, forestry and fishery workers; and crafts and related trades workers (e.g. construction workers). The correlation between occupational and leisure-time cold climate exposure was low. Men reported more occupational exposure to hand-arm vibration than women, but the correlation between occupational cold and vibration exposure was low. A range of neurological and vascular hand symptoms were statistically associated with high cold exposure, such as decreased perception to touch, warmth, and cold, as well as Raynaud’s phenomenon. In Paper II, cold sensitivity was significantly associated with previous frostbite affecting the hands, rheumatic disease, upper extremity nerve injury, migraine, vascular disease, and high body mass index (inversely), in a multiple conditional logistic regression model. In Paper III, Raynaud’s phenomenon was significantly associated with previous frostbite affecting the hands, first degree heredity, and high body mass index (inversely), in a similar model. Previous upper extremity nerve injury was suggested as a separating trait between Raynaud’s phenomenon and cold sensitivity. In Paper IV, laser speckle contrast analysis indicated disturbances in microvascular regulation, while physical examination and thermal quantitative sensory testing mainly yielded normal results. In Paper V, the 95th percentile for the Cold intolerance symptom severity score was 49.5 for men, and 53.0 for women.Conclusions: Cold exposure in the working-age population of northern Sweden varied with age, gender, occupation, and place of residence. Cold exposure was related to the reporting of neurological and vascular hand symptoms in the population as a whole. There was a major overlap between reporting cold sensitivity and Raynaud’s phenomenon, and the conditions shared several associated factors. Previous upper extremity nerve injury was suggested to be a separating trait, supporting the neurosensory pathophysiological hypothesis for cold sensitivity. Cold sensitivity was not effectively assessed by physical examination or thermal quantitative sensory testing. However, laser speckle contrast analysis could prove a useful tool in further studies on cold sensitivity. A Cold intolerance symptom severity score above 50 could be considered to indicate abnormal cold sensitivity, and be used to guide further care.
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| 2. |
- Stjernbrandt, Albin, et al.
(author)
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Cold sensitivity and associated factors : a nested case–control study performed in Northern Sweden
- 2018
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In: International Archives of Occupational and Environmental Health. - : Springer-Verlag New York. - 0340-0131 .- 1432-1246. ; 91:7, s. 785-797
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Journal article (peer-reviewed)abstract
- Aim To identify possible risk factors for cold sensitivity, by comparing cases to controls with regard to demographic and anthropometric characteristics, previous illnesses and injuries as well as ambient exposures.Methods Through a questionnaire responded to by the general population (n=12,627) cold sensitivity cases (n=502) and matched controls (n=1,004) were identified and asked to respond to a second questionnaire with focus on different aspects of cold sensitivity, hereditary factors, previous diseases, medication, tobacco use as well as exposure to ambient cold climate and hand-arm vibration (HAV).Results In total, 997 out of 1506 study subjects answered the second questionnaire, 374 cases and 623 match controls. Identified risk factors among the cases were frostbite of the hands Odds Ratio (OR) 10.3 (95% confidence interval (CI) 5.5-19.3), rheumatic disease OR 3.1 (95% CI 1.7-5.7), upper extremity nerve injury OR 2.0 (95% CI 1.3-3.0), and vascular disease OR 1.9 (95% CI 1.2-2.9). Sex differences in risk factors were HAV exposure for men and cold exposure for women increased the risk of cold sensitivity. Rheumatic diseases and migraine increased the risk of cold sensitivity among women but not among men.Conclusions The present study shows that cold sensitivity is associated with both inherent factors, acquired conditions and external exposures. Among acquired conditions, frostbite, vascular disease, nerve injury, joint disorders and migraine are significantly related to the reporting of cold sensitivity. Among external exposures, both cold climate and HAV exposure are significantly associated to cold sensitivity, and thus suitable targets for primary preventive measures. There was a difference in risk factors related to sex. HAV exposure for men and cold exposure for women increased the risk of cold sensitivity.
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| 3. |
- Stjernbrandt, Albin, et al.
(author)
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Defining abnormal cold sensitivity using the Cold Intolerance Symptom Severity questionnaire : a population study
- 2021
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In: Journal of Hand Surgery, European Volume. - : Sage Publications. - 1753-1934 .- 2043-6289. ; 46:7, s. 731-737
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Journal article (peer-reviewed)abstract
- Cold sensitivity, a common and disabling sequela of hand injury, can be assessed using the Cold Intolerance Symptom Severity (CISS) questionnaire, rating symptoms on a scale from 4 to 100. The primary objective of this study was to define a clinical cut-off for abnormal cold sensitivity based on the CISS score in a healthy working-age population. The secondary objective was to investigate how age, gender and previous injuries and diseases influence CISS scoring. In this study, 1239 out of 1582 selected healthy subjects of working age living in northern Sweden completed the questionnaire, yielding a response rate of 78%. The 95th percentile for the CISS score was 49.5 for men and 53.0 for women. The effects of age, gender and previous injuries and diseases were minor and not considered clinically relevant. The results support that a CISS score above 50 should be considered as abnormal cold sensitivity. Level of evidence: III
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| 4. |
- Stjernbrandt, Albin, et al.
(author)
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Incidence, remission, and persistence of Raynaud’s phenomenon in the general population of northern Sweden : a prospective study
- 2022
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In: BMC Rheumatology. - : BioMed Central. - 2520-1026. ; 6:1
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Journal article (peer-reviewed)abstract
- Background: Raynaud’s phenomenon is common condition, but little is known about the natural course. The primary aim of this study was to determine the incidence, remission, and persistence proportions of Raynaud’s phenomenon in the general population of northern Sweden. Secondary aims were to determine how individual and exposure factors affect the course of Raynaud’s phenomenon, and to assess gender differences.Methods: A prospective, survey-based, closed-cohort study was conducted on a sample of men and women between 18–70 years of age, living in northern Sweden. Data on Raynaud’s phenomenon characteristics and general health status were collected during the winters of 2015 (baseline) and 2021 (follow-up). Rates of incidence, remission, and persistence were calculated. Binary logistic regression was used to determine the association between baseline variables and the course of Raynaud’s phenomenon. Results: The study population consisted of 2703 women (53.9%) and 2314 men. There were 390 women (14.5%) and 290 men (12.7%) reporting Raynaud’s phenomenon in the follow-up survey. The annual incidence proportion was 0.7% among women and 0.9% among men (gender difference p = 0.04). The annual remission proportion was 4.4% and 5.5%, respectively (p = 0.05). Having sustained a cold injury affecting the hands since baseline was significantly associated with incident Raynaud’s phenomenon (OR 3.92; 95% CI 2.60–5.90), after adjusting for age and gender.Conclusions: In the general population of northern Sweden, Raynaud’s phenomenon is a common but variable condition, where symptoms may remit over time. Men had a higher incidence proportion than women. The results support a possible causal pathway where cold injury can precede the onset of Raynaud’s phenomenon.
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| 5. |
- Stjernbrandt, Albin, et al.
(author)
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Manifestations of cold sensitivity : a case series
- 2020
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In: International Journal of Circumpolar Health. - : Taylor & Francis. - 1239-9736 .- 2242-3982. ; 79:1
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Journal article (peer-reviewed)abstract
- Objectives: To characterise cold sensitivity using a semi-structured interview, physical examination, thermal quantitative sensory testing (QST), and laser speckle contrast analysis (LASCA).Methods: Eight women and four men, ages 22–74, with cold sensitivity were interviewed andexamined by an occupational physician. Thermal perception thresholds were established using QST, on the pulp of the index and little finger of the most affected hand. Skin perfusion in the dorsum of the hand was measured using LASCA, at baseline, after two-minute 12°C water immersion, and during rewarming.Results: The physical examination yielded few findings indicative of vascular or neurosensory pathology. One subject (8%) had impaired thermal perception thresholds. LASCA at baseline showed absent proximal-distal perfusion gradients in six subjects (50%), and a dyshomogeneousperfusion pattern in five (42%). Perfusion on a group level was virtually unchanged by cold stress testing (median 52.5 PU; IQR 9.0 before versus 51.3 PU; IQR 27.2 afterwards).Conclusions: Physical examination and thermal QST offered little aid in diagnosing cold sensitivity, which challenges the neurosensory pathophysiological hypothesis. LASCA indicated disturbances in microvascular regulation and could prove a useful tool in future studies on cold sensitivity.
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| 6. |
- Stjernbrandt, Albin, et al.
(author)
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Neurosensory and vascular symptoms and clinical findings in the hands of Arctic open-pit miners in Sweden and Norway : a descriptive study
- 2023
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In: International Journal of Circumpolar Health. - : Taylor & Francis. - 1239-9736 .- 2242-3982. ; 82:1
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Journal article (peer-reviewed)abstract
- This cross-sectional study aimed to describe exposure to cold climate and hand-arm vibration (HAV) as well as neurosensory and vascular symptoms and clinical findings among open-pit Arctic miners. It was based on data from questionnaires and physical examinations, including 177 men and 75 women from two open-pit mines in Sweden and Norway (response rate 54%). Working outdoors or in an unheated building or machine for at least two hours per day was reported by 44% and HAV exposure of the same duration by 10%. Neurosensory symptoms (e.g. reduced perception of touch) in the hands were reported by 47% and Raynaud’s phenomenon by 14%. In brief conclusion, the study showed that Arctic miners were commonly exposed to both cold temperatures and HAV. They also reported a broad range of neurosensory and vascular symptoms in their hands and had abnormal clinical findings related to the symptoms. The results emphasise the need for additional preventive measures in this occupational setting.
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| 7. |
- Stjernbrandt, Albin, et al.
(author)
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Raynaud's phenomenon in Northern Sweden : a population-based nested case-control study
- 2019
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In: Rheumatology International. - : Springer. - 0172-8172 .- 1437-160X. ; 39:2, s. 265-275
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Journal article (peer-reviewed)abstract
- The aim of this study was to determine the association between individual and external exposure factors, and the reporting of Raynaud’s phenomenon, with or without concomitant cold sensitivity. In a population-based nested case–control study, cases with Raynaud’s phenomenon (N = 578), and matched controls (N = 1156), were asked to respond to a questionnaire focusing on different risk factors. Univariate and multiple conditional logistic regression were performed. Analyses were stratified according to whether the cases reported cold sensitivity or not. In total, 1400 out of 1734 study subjects answered the questionnaire (response rate 80.7%). In the final multiple model, the factor with the strongest association to Raynaud’s phenomenon, with and without cold sensitivity, was previous frostbite affecting the hands (OR 12.44; 95% CI 5.84–26.52 and OR 4.01; 95% CI 1.78–9.01, respectively). Upper extremity nerve injury was associated to reporting Raynaud’s phenomenon and cold sensitivity (OR 2.23; 95% CI 1.29–3.85), but not Raynaud’s phenomenon alone. Reporting any exposure to hand-arm vibration or cumulative cold exposure was significant in univariate analyses for cases with both Raynaud’s phenomenon and cold sensitivity, but not in the multiple model. Raynaud’s phenomenon is strongly associated to previous cold injury, with a larger effect size among those who also report cold sensitivity. The fact that only upper extremity nerve injury differed significantly between case groups in our multiple model offers additional support to the neural basis for cold sensitivity.
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| 8. |
- Stjernbrandt, Albin, et al.
(author)
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Raynaud's phenomenon in the feet of Arctic open-pit miners
- 2024
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In: International Journal of Circumpolar Health. - : Taylor & Francis. - 1239-9736 .- 2242-3982. ; 83:1
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Journal article (peer-reviewed)abstract
- The literature on Raynaud's phenomenon (RP) in the feet is scarce, especially in the occupational setting. The primary aim of our study was to investigate the occurrence of RP in the feet of miners. As part of the MineHealth project, written surveys and clinical examinations were completed by 260 Arctic open-pit miners working in northern Sweden and Norway (participation rate 53.6%). Data on RP were collected using standardised colour charts and questionnaire items. Clinical examination included assessing the perception of vibration and pain in both feet. There were eight women and three men who reported RP in the feet. Four also had RP in their hands but none acknowledged any first-degree relatives with the condition. Nine reported exposure to foot-transmitted vibration and one to hand-arm vibration. Seven showed signs of neurosensory injury in the feet. To conclude, the occurrence of RP in the feet of miners was 4.4%. Most cases with RP in the feet did not report the condition in the hands and were exposed to vibration transmitted directly to the feet. There were no reports of a hereditary component. Most cases with RP in the feet also had clinical findings suggestive of peripheral neuropathy in the feet.
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