Table 1.
A list of large descriptive case series of KD in the literature (non-exhaustive list)
| Author | Aim | Methodology, level of evidence | Population | evaluation parameters | Most significant results |
|---|---|---|---|---|---|
| Dejager et al., 2002 [22] | Description of endocrine and metabolic changes |
Monocentric cohort study Level of evidence: IV |
22 KD | Gynecomastia, blood hormonal, lipid and glucose assessment | Gynecomastia in 73% of cases, infertility or decrease of testicular volume in 60%, elevation of total cholesterol, LDL-C and triglycerides (54, 40 and 48%, respectively). |
| Sperfeld et al., 2005 [23] | Evaluation of the incidence of laryngospasm |
Monocentric cohort study Level of evidence: IV |
49 KD | Symptom questionnaire, respiratory tests | 47% of the KD patients experienced laryngospasm. |
| Atsuta et al., 2006 [24] | Description of the natural history of KD |
Multicentre cohort study Level of evidence: IV |
223 KD | Clinical and biological parameters, Rankin score | Inverse correlation between the number of CAG repeats and the age of onset of symptoms |
| Chahin et al., 2008 [25] | Evaluation of functional decline and prognosis | Single centre case-control study Level of evidence: III |
39 KD 70 Controls |
10-year survival rate and functional status (ALSFRS-R) at last follow-up | Survival rate of KD was not significantly altered compared with controls (82% vs 95%, p = 0.053). The functional status was relatively preserved. Patients are mostly limited for climbing the stairs. Bulbar symptoms in all patients but no need for gastrostomy. Non-invasive ventilation was needed in one single patient. |
| Rhodes et al., 2009 [26] | Description of the natural history of KD | Single centre cohort study, patients participating in the Dudasteride therapeutic trial. Level of evidence: IV | 57 KD | Neurophysiological, biological, neuropsychological and quality of life parameters | Long diagnostic delay (5 years). Correlation between androgen levels and muscle strength. |
| Soukup et al., 2009 [27] | Evaluation of cognition changes in KD | Monocentric case-control study Level of evidence: III |
20 KD 20 Controls |
Neuropsychological assessment evaluating executive functions, memory, attention | Existence of a subclinical impairment of frontal and temporal functions |
| Hashizume [28] | Characterisation of the natural history of KD |
Monocentric cohort study Level of evidence: IV |
34 KD | Quantitative outcome measures including functional and blood parameters |
Disease progression is not affected by CAG repeat length Objective motor functional tests such as the 6-min walk test and grip power or serum creatinine levels are more sensitive at an early stage than by the functional rating scales |
| Araki et al., 2014 [29] | Evaluation of ECG abnormalities |
Monocentric cohort study Level of evidence: IV |
144 KD | ECG parameters | ECG abnormalities in 49% of cases, mainly consisting in ST segment anomalies in V1-V3 (19%) and V5-V6 (18%). Brugada syndrome (12%) with two cases of sudden death |
| Querin et al., 2015 [30] | Characterisation of the extraneurological profile of KD |
Multicentre cohort study Level of evidence: IV |
73 KD | Biology, androgen sensitivity index, genito-urinary symptoms, dual-energy X-ray absorptiometry, muscle biopsy | Androgen insensitivity. Increased prevalence of genito-urinary symptoms and diminution of bone mass. |
| Bertolin et al., 2016 [31] | Genotype-phenotype associations |
Multicentre cohort study Level of evidence: IV |
159 KD | Correlation between the number of CAG repeats and motor function | No genotype/phenotype correlations |
| Nordenvall et al., 2016 [32] | Establishing the incidence of hypospadias |
Data analysis from a national KD registry Level of evidence: IV |
4 KD | Association between hypospadia and KD | Hypospadia in KD may be underestimated |
| Francini-Pesenti, 2018 [33] | Evaluating the prevalence of metabolic syndrome |
Monocentric cohort study Level of evidence: IV |
47 KD |
Metabolic syndrome Insuline resistance Non-alcoholic liver disease |
High prevalence of insulin resistance, metabolic syndrome and non-alcoholic liver disease and NAFLD in SBMA patients |
| Rosenbohm et al., 2018 [34] | Evaluating the prevalence of metabolic changes |
Monocentric cohort study Level of evidence: IV |
80 KD | Panel of 28 laboratory parameters | Diabetes, hyperlipidemia and androgen insensitivity |
| Marcato et al., 2018 [35] | Establishing the prevalence of cognitive changes |
Monocentric cohort study Level of evidence: IV |
64 KD | Battery of neuropsychological test | Absence of neuropsychological abnormalities |
| Spinelli et al., 2019 [36] | Characterising cerebral radiological alterations | Monocentric case-control study. Level of evidence: III |
25 KD 24 Healthy 25 ALS 35 Lower motor neuron-predominant conditions |
MRI parameters: cortical thickness and diffusion tensor imaging (DTI) | Absence of abnormalities of the cerebral gray and white matters in KD patients. |
Abbreviation: ECG electrocardiogram, ENMG electroneuromyogram, MRI magnetic resonance imaging