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51/100

✓ Peer-reviewed alzhub usefulness score 51 out of 100. How common it is

Topic: Risk, prevention and care in population studies

Background A previous cross sectional study found over-representation of a postural instability gait difficulty (PIGD) motor subtype in Parkinson's disease patients with dementia (PDD) and dementia with Lewy bodies (DLB), compared with Parkinson's disease (PD). Aims (1) To examine rates of cognitive and motor decline over two years in PD (n=40), PDD (n=42) and DLB (n=41) subjects, compared with age matched controls (n=41), (2) to record whether motor phenotypes of PD, PDD, and DLB subjects changed during the study, (3) to find out if cognitive and motor decline in PD was associated with baseline motor subtype, and (4) to report the incidence of dementia in PD patients in relation to baseline motor subtype. Results Most of PDD and DLB participants were PIGD subtype at baseline assessment. In the non-demented PD group, tremor dominant (TD) and PIGD subtypes were more evenly represented. Cognitive decline over two years was greater in PDD and DLB groups (mean decline in MMSE -4.5 and -3.9, respectively), compared with PD (-0.2) and controls (-0.3). There was an association between PIGD subtype and increased rate of cognitive decline within the PD group. Of 40 PD patients, 25% of the 16 PIGD subtype developed dementia over two years, compared with none of the 18 TD or six indeterminate phenotype cases (chi2=6.7, Fisher's exact test p Conclusion A PIGD motor subtype is associated with a faster rate of cognitive decline in PD and may be considered a risk factor for incident dementia in PD.

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APA 7th

Burn, D. J., Rowan, E. N., Allan, L. M., Molloy, S., O'Brien, J. T., & McKeith, I. G. (2006). Motor subtype and cognitive decline in Parkinson's disease, Parkinson's disease with dementia, and dementia with Lewy bodies. Journal of neurology, neurosurgery, and psychiatry. https://doi.org/10.1136/jnnp.2005.081711

Vancouver

Burn DJ, Rowan EN, Allan LM, Molloy S, O'Brien JT, McKeith IG. Motor subtype and cognitive decline in Parkinson's disease, Parkinson's disease with dementia, and dementia with Lewy bodies. Journal of neurology, neurosurgery, and psychiatry. 2006. doi:10.1136/jnnp.2005.081711. PMID: 16614017.

BibTeX

@article{burn2006-16614017,
  author  = {Burn, D. J. and Rowan, E. N. and Allan, L. M. and Molloy, S. and O'Brien, J. T. and McKeith, I. G.},
  title   = {{Motor subtype and cognitive decline in Parkinson's disease, Parkinson's disease with dementia, and dementia with Lewy bodies}},
  journal = {Journal of neurology, neurosurgery, and psychiatry},
  year    = {2006},
  doi     = {10.1136/jnnp.2005.081711},
  pmid    = {16614017},
  url     = {https://doi.org/10.1136/jnnp.2005.081711}
}

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Key findings

Background A previous cross sectional study found over-representation of a postural instability gait difficulty (PIGD) motor subtype in Parkinson's disease patients with dementia (PDD) and dementia with Lewy bodies (DLB), compared with Parkinson's disease (PD).
Aims (1) To examine rates of cognitive and motor decline over two years in PD (n=40), PDD (n=42) and DLB (n=41) subjects, compared with age matched controls (n=41), (2) to record whether motor phenotypes of PD, PDD, and DLB subjects changed during the study, (3) to find out if cognitive and motor decline in PD was associated with baseline motor subtype, and (4) to report the incidence of dementia in PD patients in relation to baseline motor subtype.
Results Most of PDD and DLB participants were PIGD subtype at baseline assessment.
Cognitive decline over two years was greater in PDD and DLB groups (mean decline in MMSE -4.5 and -3.9, respectively), compared with PD (-0.2) and controls (-0.3).
Of 40 PD patients, 25% of the 16 PIGD subtype developed dementia over two years, compared with none of the 18 TD or six indeterminate phenotype cases (chi2=6.7, Fisher's exact test p<0.05).

Why it matters

In people with Parkinson's disease, a postural instability gait difficulty motor subtype was associated with faster cognitive decline and higher incidence of dementia over two years. This describes a risk marker within Parkinson's disease and does not test any treatment.

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Study details

Participants40
Evidence strengthLow

How this study scored 51/100

Published in a peer-reviewed journal. Scored zero for study design, effect reported and randomized / blinded because the record does not state it.

Component	Points	Why
Journal tier	7 / 10	Tier 3 — peer-reviewed journal (Journal of neurology, neurosurgery, and psychiatry)
Journal's citation record	3 / 4	Journal of Neurology Neurosurgery & Psychiatry: journal h-index 336 (OpenAlex, 2026-10-29)
Study design	0 / 12	No study design recorded — scores zero, not guessed (not stated in the record — scored 0)
Strength of evidence	1 / 5	Rated “low” in our summary
Peer-review validation	10 / 10	Peer-reviewed. Published as an article in a named peer-reviewed journal.
How recent	1 / 5	2006 — older than 20 years, still counted
Sample size	1 / 4	40 participants
Effect reported	0 / 3	No effect size reported — scores zero (not stated in the record — scored 0)
Studied in people	3 / 3	Studied in people (participant count stated)
Randomized / blinded	0 / 2	No randomization or blinding stated — scores zero (not stated in the record — scored 0)
Times cited	6 / 7	Cited 436 times (OpenAlex, 2026-10-10)
Citations per year	3 / 5	19.8 citations a year over 22 year(s) since 2006
Impact for its field and year	4 / 6	Cited 11.5× the average for papers of its field and year (OpenAlex FWCI)
Cited by studies here	3 / 6	Cited by 14 other studies in this library
Still being cited	2 / 4	Cited 38 times in 2024–2026 (2026 still in progress; OpenAlex)
Senior author's track record	4 / 4	Last-listed author David John Burn: h-index 120 (OpenAlex, whole career)
Institution's track record	1 / 3	Newcastle University: institution h-index 932 (OpenAlex)
Multicenter collaboration	0 / 3	OpenAlex lists 1 institution(s) in 1 country — scores zero (affiliation lists can be incomplete)
Indexed in PubMed	2 / 2	Indexed in PubMed (PMID 16614017)
Free to read	0 / 2	Behind a paywall — scores zero
Total	51 / 100	—

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